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Transcript of Computer Sciences – 2022
List of Contents
Page No.
Chapter One Computer Basics
2 1. Introduction
2 2. Computer Science
2 3. Basics of Computer
3 3.1 What is a Computer?
3 3.2 Functions of Computer
6 3.3 Data and Information
7 3.4 History of Computers
10 3.5 Characteristics of Computer System
11 3.6 Basic Applications of Computer
16 4. Computer Classification
20 5. Components of Computer System
20 5.1 Computer Hardware
42 5.2 Computer Software
45 6. Computer Numbering Systems
49 7. Programming Languages
51 8. Information Technology
Chapter Two
Computer Networks
55 1. Computer Network
60 2. Internet
62 3. Web Browsing Software
66 4. E- Mail
Chapter Three
Computer Viruses and Crimes
67 1. Computer Viruses
69 2. Computer Crimes
70 Chapter Four
Getting Started with Windows
96 Chapter Five
Working with Files
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1. Introduction
Computer Science is one of the disciplines of modern science under which, we
study about the various aspects of computer technologies, their development, and their
applications in the present world. Computer Science includes a wide range of topics such
as the software engineering, networking, artificial intelligence, development of Computer
Technology (hardware and software), applications of Computer in today‟s life, information
technology, computer threat, computer security, etc. However, we have segregated this
tutorial into different chapters for easy understanding.
Our Computer sciences tutorial includes all topics of Computer fundamentals such as input
devices, output devices, memory, CPU, motherboard, computer network, virus, software,
hardware etc.
2. Computer Science The science that deals with the theory and methods of processing information in
digital computers, the design of computer hardware and software, and the applications of
computers. The discipline of computer science includes the study of algorithms and data
structures, computer and network design, modeling data and information processes, and
artificial intelligence. Computer science draws some of its foundations from mathematics
and engineering and therefore incorporates techniques from areas such as queuing theory,
probability and statistics, and electronic circuit design. Computer science also makes heavy
use of hypothesis testing and experimentation during the conceptualization, design,
measurement, and refinement of new algorithms, information structures, and computer
architectures.
An algorithm is a detailed and unambiguous sequence of actions for solving a
problem or for performing some task. Algorithms are essential to the way computers
process information because a computer program is basically just an algorithm that tells
the computer what specific steps to perform (and in what sequence) in order to carry out a
specified task. Principal areas of study within Computer Science include artificial
intelligence, computer systems and networks, security, database systems, human computer
interaction, vision and graphics, numerical analysis, programming languages, software
engineering, bioinformatics and theory of computing.
3. Basics of Computer In today's world, we use computers for all our tasks. Our day-to-day activities:
paying bills, buying groceries, using social media, seeking entertainment, working from
home, communicating with a friend, etc., can all be done using a computer. So, it is
important not only to know how to use a computer, but also to understand the components
of a computer and what they do.
This topic explains all concepts related to computer in detail, from origin to end.
The idea of computer literacy is also discussed, which includes the definition and
functions of a computer and learn about the components of a computer, the concept of
hardware and software, representation of data/information, the concept of data processing
and applications of Information.
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3.1 What is a Computer?
A computer is a programmable electronic device that accepts raw data as input
and processes it with a set of instructions (a program) to produce the result as output, it
renders output just after performing mathematical and logical operations and can save the
output for future use. It can process numerical as well as non-numerical calculations. The
term "computer" is derived from the Latin word "computare" which means to calculate.
A computer is designed to execute applications and provides a variety of solutions
through integrated hardware and software components. It works with the help of programs
and represents the decimal numbers through a string of binary digits. It also has a memory
that stores the data, programs, and result of processing. The components of a computer
such as machinery that includes wires, transistors, circuits, hard disk are called hardware.
Whereas, the programs and data are called software.
Computer
3.2 Functions of Computer
There are necessary functions of computer that needs to perform by the computer
itself for completing all the task. Not every PC owner knows about the specific functions
the corresponding computing device performs. Basically, a computer is an electronic
machine, used for processing and storing, the data given by the user. There are different
types of computers from micro to supercomputers. Some have many functions with
complexity while the basic computer has only 4 functions. So, this article explains the
basic functionality of the computer system as well as the functions of each component.
In the most general sense, The Four Basic Functions of Computers are: –
1. Input Function
2. Processing Data
3. Data Storage
4. Output Function
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Functions of Computer
Let‟s understand all the 4 Basic functions of computer easily, be with me:
1. Input Function
Input is the process of entering any type of data and instructions into a computer
system by using the input devices such as a Keyboard, Mouse, Scanner, Microphone, etc,
in order to receive user signals to the computer. We use such input devices to input the
data into the computer by typing the words and sentences through the keyboard, by
scrolling and clicking the buttons through the mouse, recording the audio and video
through microphone and camera, etc.
By using these input devices, we can perform the basic tasks in computer-like calculations,
viewing the images and videos, listening to the audios, preparing the PPT documents,
browsing the Internet. In fact, all the basic functions of a computer user are initiated by
inputting the data into the computer through input devices.
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2. Processing Data
This processing function is the 2nd step that offers the process and handling of the
input data instructed by the user. To process the user input data computer needs a‟ Central
Processing Unit„ (CPU). The computer CPU, of course, is primarily obliged to entire
process data of the computer. The CPU takes data and instructions from the input devices
and performs all types of calculations based on the instructions given.
It consists of manipulating the data in different ways, performing calculations, modifying
the instructions, coding, and executing the actions. All this process is done on the
motherboard with the help of the processor, power supply unit and RAM presented in the
CPU.
3. Data Storage
The computer must store the data permanently so that it is available while
processing data temporarily. The function of data storage is an important component for
the proper functioning of computer systems. Basically, there are two types of storage in the
CPU of a Computer – One is RAM (used for processing the input data temporarily )
and the second is ROM (used to store processed data permanently).
4. Output Function
The fourth and last function of the computer is the output that means the results
generated by the computer once the processing of CPU is completed, based on the
instruction given by the user. The output is in the form of documents, videos, audio, graphs,
images, etc. that you see from the output devices such as computer monitor, printer,
speakers, headphones, screen projector, etc. Thus, now all the results are displayed on your
computer screen.
The above all are the basic and significant functions of computers for completing everyday
tasks from simple tasks like word processing, paint, recording videos PPT to complicated
tasks like playing games, videos, graphic designing, etc. The process of moving data
between a computer and the external components of the computer is called the I/O process
is done I/O Devices.
In Simple Words, the working of a computer mainly :
Step 1. Accepting the data from Input Devices – Like Keyboard, Mouse, Microphone.
Step 2. Transfer data to RAM memory in the CPU.
Step 3. Processing. Analyzing and Storing the data as per instructions.
Step 4. At last, after the process sending the results to the Output Devices – Like Monitor,
Printer, Speakers.
In short, The information and data are given to computers using Input devices in a discrete
form. The input device accepts and transfers the data to the CPU. After that, the data is
handled or processed by the CPU and stored in the Memory of the Computer. And in this
way, we get the output results of our instructions through Output Devices.
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3.3 Data and Information
Data is a collection of unorganized facts and figures and does not provide any further
information regarding patterns, context, etc. Hence data means "unstructured facts and
figures".
Information is a structured data i.e., organized meaningful and processed data. To
process the data and convert into information, a computer is used.
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3.4 History of Computers
This development period of electronic computing technology is called Computer
Generation. Computer generations are based on when major technological changes in
computers occurred, like the use of vacuum tubes, transistors, and the microprocessor. As
of 2020, there are five generations of the computer, although the sixth generation could be
in development now in the early 21st century. During the evolutionary timeline, each
generation of computers has improved a lot by undergoing considerable changes in their
size, type, and functionality.
By analyzing them, one can trace the evolution of computer technology, to see how
the computer industry has changed over the years and how great capabilities and software
progress has been made by humankind in under a hundred years, as a result, the creation of
different generations.
At present, the computer is playing a significant part in human existence because
today‟s digital computer is being used for every work in each field. If someday an issue
occurs in the computer or the server is down, at that point all the work stops. This is how
significant it is for technology development!
The brief history of computers is discussed in the next page.
1. First Generation (1940 - 1956)
The first generation of computers used vacuum tubes as a major piece of
technology. Vacuum tubes were widely used in computers from 1940 through 1956.
Vacuum tubes were larger components and resulted in first generation computers being
quite large in size, taking up a lot of space in a room. Some of the first-generation
computers took up an entire room.
The ENIAC is a great example of a first-generation computer. It consisted of nearly 20,000
vacuum tubes, as well as 10,000 capacitors and 70,000 resistors. It weighed over 30 tons
and took up a lot of space, requiring a large room to house it. Other examples of first
generation computers include the EDSAC, IBM 701, and Manchester Mark 1.
Vacuum tubes
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2. Second Generation (1956 - 1963)
The second generation of computers saw the use of transistors instead of vacuum
tubes. Transistors were widely used in computers from 1956 to 1963. Transistors were
smaller than vacuum tubes and allowed computers to be smaller in size, faster in speed,
and cheaper to build. The first computer to use transistors was the TX-0 and was
introduced in 1956. Other computers that used transistors include the IBM 7070, Philco
Transac S-1000, and RCA 501.
Transistors
3. Third Generation (1964 - 1971)
The third generation of computers introduced the use of IC (integrated circuits) in
computers. Using IC's in computers helped reduce the size of computers even more
compared to second-generation computers, as well as make them faster.
Nearly all computers since the mid to late 1960s have utilized IC's. While the third
generation is considered by many people to have spanned from 1964 to 1971, IC's are still
used in computers today. Over 45 years later, today's computers have deep roots going
back to the third generation.
Integrated circuits
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4. Fourth Generation (1972-2010)
The fourth generation of computers took advantage of the invention of the
microprocessor, more commonly known as a CPU. Microprocessors, along with
integrated circuits, helped make it possible for computers to fit easily on a desk and for
the introduction of the laptop. Some of the earliest computers to use a microprocessor
include the Altair 8800, IBM 5100, and Micral. Today's computers still use a
microprocessor, despite the fourth generation being considered to have ended in 2010.
Microprocessor
5. Fifth Generation (2010-Present)
The fifth generation of computers is beginning to use AI (artificial intelligence),
an exciting technology that has many potential applications around the world. Leaps have
been made in AI technology and computers, but there is still room for much improvement.
One of the more well-known examples of AI in computers is IBM's Watson, which was
featured on the TV show Jeopardy as a contestant. Other better-known examples include
Apple's Siri on the iPhone and Microsoft's Cortana on Windows 8 and Windows 10
computers. The Google search engine also utilizes AI to process user searches.
Robots
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3.5 Characteristics of Computer System
The characteristics of the computer system are as follows −
2.4.1 Speed
A computer works with much higher speed and accuracy compared to humans
while performing mathematical calculations. Computers can process millions
(1,000,000) of instructions per second. The time taken by computers for their
operations is microseconds and nanoseconds.
2.4.2 Accuracy
Computers perform calculations with 100% accuracy. Errors may occur due to
data inconsistency or inaccuracy.
2.4.3 Diligence
A computer can perform millions of tasks or calculations with the same
consistency and accuracy. It doesn‟t feel any fatigue or lack of concentration. Its
memory also makes it superior to that of human beings.
2.4.4 Versatility
Versatility refers to the capability of a computer to perform different kinds of
works with same accuracy and efficiency.
2.4.5 Reliability
A computer is reliable as it gives consistent result for similar set of data i.e., if
we give same set of input any number of times, we will get the same result.
2.4.6 Automation
Computer performs all the tasks automatically i.e., it performs tasks without
manual intervention.
2.4.7 Memory
A computer has built-in memory called primary memory where it stores data.
Secondary storage are removable devices such as CDs, pen drives, etc., which are also
used to store data.
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3.6 Basic Applications of Computer
Computers are playing a vital role in almost every field and making our day-to-day
tasks more manageable. Computers were only used to perform complex numerical
calculations in a previous time, but they have reached too far and now perform many
different roles. They are now performing diverse set functions from complicated
calculations to generating business reports, bill generation to education, programming or
development to entertainment, etc.
Because of their characteristics and powerful functionalities, computers are used in various
fields, such as homes, businesses, government offices, research organizations, educational
institutions, medical, entertainment, etc. Computers have taken industries and businesses to
a whole new level. In this article, we have elaborated the most common uses of computers
in different fields:
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2.5.1 Business
Currently, computers can be seen in almost every business. Computers are almost
part of a business setup because they increase productivity and help race in a competitive
environment. In businesses, computers are primarily used to store and manage accounts
and personal data, maintain projects, track inventory status, and make reports and
presentations. Besides, computers are best suited for transaction processing because they
are more accurate and faster than humans. Computers also help people analyze their
investment, expenses, profits, sales and many other aspects of the business.
2.5.2 Science
Scientists are amongst one of those people who use computers as their primary
work tool. In science, research and engineering, computers are best suited for collecting,
analyzing, categorizing, and storing the data. They also help scientists to exchange data
with each other both internally and internationally. Computers enable scientists from
different locations (such as different countries) to work together on the same project with
cloud support. Besides, computers play a crucial role in launching, maintaining, controlling
spacecraft, and operating many other technologies.
2.5.3 Government
In the government sector, computers are beneficial. They are getting used to
performing various functions in different departments and improving their services'
quality, efficiency, and productivity. Some examples of such services are city planning,
traffic control, law enforcement, infrastructure developments, and tourism. In most cases,
the primary purposes of using computers are performing data processing tasks, maintaining
citizens' database, and promoting a paperless environment. Apart from this, computers are
playing a crucial role in the country's defense system. They are helping in missile
development, rocket, satellite launches, etc.
2.5.4 Health and Medical
Computers are radically changing the methods of diagnosis in hospitals. They are
used for maintaining patients' information, records, live monitoring of patients, X-rays, and
more. Everything is being digitized with the help of computers. Computers help configure
lab-tools, monitor heart rate, and blood pressure, etc. Doctors get extra advantages in
treating patients with proper drugs and medicines. Additionally, computers enable doctors
to exchange patient's data easily with other medical specialists. Besides, advanced surgical
devices are based on robotics that helping surgeons to conduct complex operations and
surgeries remotely.
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2.5.5 Education
Computers are broadly getting used in the education field. They help people get
different educational materials (such as images, videos, e-books, etc.) in one place. All
such information can be accessed through the Internet. Additionally, computers are best
suited for online classes, online tutoring, online examinations, and creating assignments
and projects. Apart from this, they can also be used to maintain and monitor student
performance and other information.
2.5.6 Industry
Computers are used in industries to perform various tasks, such as maintaining inventory,
interior designing, designing samples or virtual products, communicating over video
conferencing, and more. Online marketing has made it easier for people to buy products in
rural areas. Online trading in stock markets has also seen a significant revolution due to its
easy participation potential. Computers have enabled people from different levels of
different locations to participate easily in stock marketing.
2.5.7 Banking
Banking has become so advanced in the past few years. Most countries use online
banking systems where customers can access their data directly using computers and the
Internet. People can check their account balance, transfer money, and pay online bills,
including credit cards. Besides, Banks use computers to perform transactions and store
customer data, transaction records, etc. Banks have reduced the number of manual errors,
number of employees, and costs to a great extent by using computers. ATMs are the best
example of computers that are helping people to withdraw and deposit the money
themselves.
2.5.8 Entertainment
Computers nowadays are one of the best mediums for entertainment. Computers
can be used to watch movies, play games, listen to music, etc. Computers combined with
MIDI instruments can be used to record audio through artificial instruments. Besides,
people can also enjoy recording their videos with webcam and apply several entertaining
AI effects. Several Photo editor programs are also available with fabulous powerful
features.
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2.5.9 Training
Most companies use computers to provide training to their employees. Computer-based
training helps companies save their time, money, and increase productivity. Also,
computer-based training can be used to train employees for large distances in various
locations. This will eliminate travel time and costs, making the training process much more
comfortable and smoother.
2.5.10 Arts
Computers have become part of art, photography, dance, and culture. Computers
with advanced features allow users to draw their projects directly on it. Besides, people can
use computers to digitize their photos. There are several photo editor software that can help
people edit and customize their photos. Apart from this, the dance's movements and steps
can be shown live with animations' help.
2.5.11 Sports
In today's technologically developed world, computers are being used in almost
every sport. There are many sports activities where computers are making things possible.
In sports, computers are mainly used to maintain scoreboards, records, and other statistics.
Furthermore, they are used to analyze player movements and make various in-game
decisions. Computers help make complex in-game decisions (especially in umpiring),
which cannot be seen by human eyes.
2.5.12 Robotics
Robotics is one of the emerging fields of technology that uses computers for
science and engineering as well as designing machines. These machines can be virtual
(such as software bots) and physical ones that can reduce or eliminate human workload.
Additionally, some machines can perform heavy tasks that humans cannot complete, or
that may take a long time to complete. Car manufacturing was one of the first examples
where robots helped to assemble car parts and perform many other heavy tasks. However,
nowadays, robots are beneficial in many fields, such as exploring areas where conditions
are difficult for humans, helping the military, helping law enforcement and helping health
professionals, etc.
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2.5.13 Safety and Security
Computers are capable of working together with different equipment, tools, and
technologies. When it comes to safety, computers are widely being used with the security
camera. Almost every private and government organizations are equipped with security
cameras to monitor people and goods. Also, these cameras are helping security intelligence
agencies to identify terrorists or criminals in public places. Computers attached with a
fingerprint scanner and face-recognition technology have made it harder for fraudsters to
use fake identities and take government benefits using someone else's identity. Security
systems have become so powerful with the introduction of computer technology and the
Internet.
2.5.14 Publishing
Computers are one of the first choices when it comes to publication. Computers are mainly
used for designing newsletters, novels, posters, magazines, or newspapers, etc. They are
suitable for almost every type of publication. Computers can be seen in both types of
publishing methods, either its hard-copy or e-books. Apart from this, computers play a
vital role in blogging and writing articles on websites.
2.5.15 Weather Forecasting
Weather forecasting is never easy for humans because it depends on many factors that are
continually changing. It is almost impossible for humans to predict the weather without
using a computer. The weather forecasting process involves complex computation and
monitoring of data from satellites and many other technological devices. The computer has
made it a little easier to predict weather conditions because it can process information from
different sources and make complex calculations related to it, which are necessary for
forecasting. Computers process enormous amounts of meteorological information during
weather forecasting.
2.5.16 Communication
Computers have become one of the primary sources of communication. Modern computers
come with a built-in webcam and microphone to make use of communication easier.
People can use software like Skype and Hangout to connect with other people over the
Internet. Because of the videoconferencing feature, people can connect with audio and
video. Computers help families connect to their relatives, businesses to organize meetings,
and companies to take interviews, between two different locations that are too far. Apart
from this, older communications methods such as emails are also still used widely.
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4. Computer Classification
Historically computers were classified according to processor types because
development in processor and processing speeds were the developmental benchmarks.
Earliest computers used vacuum tubes for processing, were huge and broke down
frequently. However, as vacuum tubes were replaced by transistors and then chips, their
size decreased and processing speeds increased manifold.
All modern computers and computing devices use microprocessors whose speeds and
storage capacities are skyrocketing day by day. The developmental benchmark for
computers is now their size. Computers are now classified on the basis of their use or size
Desktop
Laptop
Tablet
Server
Mainframe
Supercomputer
Let us look at all these types of computers in detail.
1. Desktop
Desktop computers are personal computers (PCs) designed for use by an
individual at a fixed location. IBM was the first computer to introduce and popularize use
of desktops. A desktop unit typically has a CPU (Central Processing Unit), monitor,
keyboard and mouse. Introduction of desktops popularized use of computers among
common people as it was compact and affordable.
Personal Computer
Riding on the wave of desktop‟s popularity many software and hardware devices were
developed specially for the home or office user. The foremost design consideration here
was user friendliness.
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2. Laptop
Despite its huge popularity, desktops gave way to a more compact and portable personal
computer called laptop in 2000s. Laptops are also called notebook computers or
simply notebooks. Laptops run using batteries and connect to networks using Wi-Fi
(Wireless Fidelity) chips. They also have chips for energy efficiency so that they can
conserve power whenever possible and have a longer life.
Modern laptops have enough processing power and storage capacity to be used for all
office work, website designing, software development and even audio/video editing.
3. Tablet
After laptops computers were further miniaturized to develop machines that have
processing power of a desktop but are small enough to be held in one‟s palm. Tablets
have touch sensitive screen of typically 5 to 10 inches where one finger is used to touch
icons and invoke applications.
Keyboard is also displayed virtually whenever required and used with touch strokes.
Applications that run on tablets are called apps. They use operating systems by Microsoft
(Windows 8 and later versions) or Google (Android). Apple computers have developed
their own tablet called iPad which uses a proprietary OS called iOS.
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4. Server
Servers are computers with high processing speeds that provide one or more services to
other systems on the network. They may or may not have screens attached to them. A
group of computers or digital devices connected together to share resources is called
a network.
Servers have high processing powers and can handle multiple requests simultaneously.
Most commonly found servers on networks include −
File or storage server
Game server
Application server
Database server
Mail server
Print server
5. Mainframe
Mainframes are computers used by organizations like banks, airlines and railways to
handle millions and trillions of online transactions per second. Important features of
mainframes are −
Big in size
Hundreds times Faster than servers, typically hundred megabytes per second
Very expensive
Use proprietary OS provided by the manufacturers
In-built hardware, software and firmware security features
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6. Supercomputer
Supercomputers are the fastest computers on Earth. They are used for carrying out
complex, fast and time intensive calculations for scientific and engineering applications.
Most common uses of supercomputers include −
Molecular mapping and research
Weather forecasting
Environmental research
Oil and gas exploration
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5. Components of Computer system
Every computer is composed of two basic components: Hardware and Software.
1. Computer hardware is the umbrella term used to describe the physical collection of
elements that complete a whole computer system. Hardware encompasses the external
tools that allow users to operate a computer, such as the keyboard, mouse and the
monitor, and internal components like the motherboard, graphics card, and hard disc.
2. Computer software is the term used to define the sets of code, data, and instructions
stored on the computer‟s hard drive that operate the machine from behind the scenes.
In other words, software allows a computer to actually perform tasks, without
software, computer hardware would be entirely useless.
5.1 Computer Hardware
The term 'Computer hardware' or 'Computer parts' is used to describe the
physical and tangible components of a computer, i.e. the components that can be seen and
touched. The components that make up hardware can be categorized as being either
internal or external. Internal components are those installed inside the computer, typical
examples being the motherboard, power supply, and central processing unit (CPU).
External components are connected to the outside of the computer, these can also be
referred to as peripherals, or peripheral devices, common examples being the monitor,
keyboard, and mouse.
There are 4 main Computer Hardware components that are given below:
A. Input devices − keyboard, mouse, etc.
B. Output devices − printer, monitor, etc.
C. Processing Devices – Central Process Unit.
D. Computer Memory – RAM, ROM, etc.
E. Other Components of Computer Hardware – Motherboard.
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Computer hardware
The operations of computer hardware components are given below:
1. Inputting: It is the process of entering raw data, instructions and information into the
computer. It is performed with the help of input devices.
2. Storing: The computer has primary memory and secondary storage to store data and
instructions. It stores the data before sending it to CPU for processing and also stores
the processed data before displaying it as output.
3. Processing: It is the process of converting the raw data into useful information. This
process is performed by the CPU of the computer. It takes the raw data from storage,
processes it and then sends back the processed data to storage.
4. Outputting: It is the process of presenting the processed data through output devices
like monitor, printer and speakers.
5. Controlling: This operation is performed by the control unit that is part of CPU. The
control unit ensures that all basic operations are executed in a right manner and
sequence.
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5.1.1 Input Devices (Input Unit)
Input device enables the user to send data, information, or control signals to a computer.
The Central Processing Unit (CPU) of a computer receives the input and processes it to
produce the output.
Example of Input unit devices: keyboard, mouse, scanner, joystick, Magnetic tape etc.
Input
Devices Characteristics Image
Keyboard
The keyboard is a basic input device that is used to enter data
into a computer or any other electronic device by pressing
keys. It has different sets of keys for letters, numbers,
characters, and functions. Keyboards are connected to a
computer through USB or a Bluetooth device for wireless
communication.
Mouse
The mouse is a hand-held input device which is used to move
cursor or pointer across the screen. It is designed to be used
on a flat surface and generally has left and right button and a
scroll wheel between them. Laptop computers come with a
touchpad that works as a mouse. It lets you control the
movement of cursor or pointer by moving your finger over the
touchpad. Some mouse comes with integrated features such as
extra buttons to perform different buttons.
Trackballs A trackball is also a pointing device which will work like a
mouse. It is mainly used for gaming and entertainment
purpose.
Digital
Pens
A digital pen is another input device which is mostly used
with tablets, PDAs, etc. A digital pen is also called as a Stylus
which helps to write or draw data over pad.
Scanners
The scanner uses the pictures and pages of text as input. It
scans the picture or a document. The scanned picture or
document then converted into a digital format or file and is
displayed on the screen as an output. It uses optical character
recognition techniques to convert images into digital ones.
Barcode
Readers
Barcode reader helps to read information which is printed as
bars in back of goods or items.
Voice
Recognition
System
Voice recognition system interprets or receives dictation or
spoken commands to authorize user.
Touch
screen
A touch screen is an input device which uses sensors to sense
touch of users to get input data.
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5.1.2 Output Devices
The output device displays the result of the processing of raw data that is entered in
the computer through an input device. There are a number of output devices that display
output in different ways such as text, images, hard copies, and audio or video.
Some of the popular output devices are:
1- Monitor
The monitor is the display unit or screen of the computer. It is the main output device that
displays the processed data or information as text, images, audio or video.
The types of monitors are given below
CRT Monitor
CRT monitors are based on the cathode ray tubes.
LCD Monitor
The LCD monitor is a flat panel screen that is compact and light-weight as compared to
CRT monitors. It is based on liquid crystal display technology which is used in the screens
of laptops, tablets, smart phones, etc.
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LED monitor
The LED monitor is an improved version of an LCD monitor. It also has a flat panel
display and uses liquid crystal display technology like the LCD monitors.
Plasma Monitor
The plasma monitor is also a flat panel display that is based on plasma display technology.
Plasma displays are brighter than liquid crystal displays (LCD) and also offer a wide
viewing angle than an LCD.
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2- Printer
A printer produces hard copies of the processed data. It enables the user, to print images,
text or any other information onto the paper. Based on the printing mechanism, the printers
are of two types: Impact Printers and Non-impact Printers.
o Impact Printers: They are of two types:
A. Character Printers
B. Line printers
o Non-impact printers: They are of two types:
A. Laser printers
B. Inkjet printers
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3- Projector
A projector is an output device that enables the user to project the output onto a
large surface such as a big screen or wall. It can be connected to a computer and similar
devices to project their output onto a screen. It uses light and lenses to produce magnified
texts, images, and videos. So, it is an ideal output device to give presentations or to teach a
large number of people.
Modern projects (digital projectors) come with multiple input sources such as HDMI ports
for newer equipment and VGA ports that support older devices. Some projectors are
designed to support Wi-Fi and Bluetooth as well. They can be fixed onto the ceiling,
placed on a stand, and more and are frequently used for classroom teaching, giving
presentations, home cinemas, etc.
4- Sound Systems
Sound systems are output devices which are used to get multimedia content such as
voice, music, etc., as output. Some of examples of sound systems are speakers,
headphones, and microphones.
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5.1.3 Processing Devices – Central Process Unit.
The Central Processing Unit (CPU) is called "the brain of computer" as it controls
operation of all parts of computer. CPU is installed or inserted into a CPU socket located
on the motherboard. Furthermore, it is provided with a heat sink to absorb and dissipate
heat to keep the CPU cool and functioning smoothly.
Generally, a CPU has three components:
o Control Unit
o ALU (Arithmetic and Logic Unit)
o Memory or Storage Unit
Central Processing Unit components
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1. Control unit: A control unit works by receiving input information that it converts into
control signals, which are then sent to the central processor. The computer's processor
then tells the attached hardware what operations to carry out. The functions that a
control unit performs are dependent on the type of CPU, due to the variance of
architecture between different manufacturers.
The following diagram illustrates how instructions from a program are processed.
Functions of Control Unit
Control unit performs following functions −
• It controls all activities of computer
• Supervises flow of data within CPU
• Directs flow of data within CPU
• Transfers data to Arithmetic and Logic Unit
• Transfers results to memory
• Fetches results from memory to output devices
2. ALU (Arithmetic and Logic Unit): It is the arithmetic logic unit, which performs
arithmetic and logical functions. Arithmetic functions include addition, subtraction,
multiplication division, and comparisons. Logical functions mainly include selecting,
comparing, and merging the data. A CPU may contain more than one ALU.
Furthermore, ALUs can be used for maintaining timers that help run the computer.
3. Memory or Storage Unit/ Registers: It is called Random access memory (RAM). It
temporarily stores data, programs, and intermediate and final results of processing. So,
it acts as a temporary storage area that holds the data temporarily, which is used to run
the computer.
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Types of CPU
CPUs are mostly manufactured by Intel and AMD, each of which manufactures its
own types of CPUs. In modern times, there are lots of CPU types in the market. Some of
the basic types of CPUs are described below:
Single Core CPU: Single Core is the oldest type of computer CPU, which was used in the
1970s. It has only one core to process different operations. It can start only one operation at
a time; the CPU switches back and forth between different sets of data streams when more
than one program runs. So, it is not suitable for multitasking as the performance will be
reduced if more than one application runs. The performance of these CPUs is mainly
dependent on the clock speed. It is still used in various devices, such as smartphones.
Dual Core CPU: As the name suggests, Dual Core CPU contains two cores in a single
Integrated Circuit (IC). Although each core has its own controller and cache, they are
linked together to work as a single unit and thus can perform faster than the single-core
processors and can handle multitasking more efficiently than Single Core processors.
Quad Core CPU: This type of CPU comes with two dual-core processors in one
integrated circuit (IC) or chip. So, a quad-core processor is a chip that contains four
independent units called cores. These cores read and execute instructions of CPU. The
cores can run multiple instructions simultaneously, thereby increases the overall speed for
programs that are compatible with parallel processing.
Quad Core CPU uses a technology that allows four independent processing units (cores) to
run in parallel on a single chip. Thus by integrating multiple cores in a single CPU, higher
performance can be generated without boosting the clock speed. However, the
performance increases only when the computer's software supports multiprocessing. The
software which supports multiprocessing divides the processing load between multiple
processors instead of using one processor at a time.
What is CPU Clock Speed?
The clock speed of a CPU or a processor refers to the number of instructions it can
process in a second. It is measured in gigahertz. For example, a CPU with a clock speed of
4.0 GHz means it can process 4 billion instructions in a second.
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5.1.4 Computer Memory
The computer memory holds the data and instructions needed to process raw data and
produce output. The computer memory is divided into large number of small parts known
as cells. Each cell has a unique address which varies from 0 to memory size minus one.
But, if we categorize memory on behalf of space or location, it is of four types:
A. Register memory
B. Cache memory
C. Primary memory
D. Secondary memory
Memory Units
Memory units are used to measure and represent data. Some of the commonly used
memory units are:
1. Bit: The computer memory units start from bit. A bit is the smallest memory unit to
measure data stored in main memory and storage devices. A bit can have only one
binary value out of 0 and 1.
2. Byte: It is the fundamental unit to measure data. It contains 8 bits or is equal to 8
bits. Thus a byte can represent 2*8 or 256 values.
3. Kilobyte: A kilobyte contains 1024 bytes.
4. Megabyte: A megabyte contains 1024 kilobytes.
5. Gigabyte: A gigabyte contains 1024 megabyte.
6. Terabyte: A terabyte contains 1024 gigabytes.
A. Register Memory
Register memory is the smallest and fastest memory in a computer. It is not a part
of the main memory and is located in the CPU in the form of registers, which are the
smallest data holding elements. A register temporarily holds frequently used data,
instructions, and memory address that are to be used by CPU. They hold instructions that
are currently processed by the CPU. All data is required to pass through registers before it
can be processed. So, they are used by CPU to process the data entered by the users.
Registers hold a small amount of data around 32 bits to 64 bits. The speed of a CPU
depends on the number and size (no. of bits) of registers that are built into the CPU.
Registers can be of different types based on their uses. Some of the widely used Registers
include Accumulator or AC, Data Register or DR, the Address Register or AR, Program
Counter (PC), I/O Address Register, and more.
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B. Cache Memory
Cache memory is a high-speed memory, which is small in size but faster than the
main memory (RAM). The CPU can access it more quickly than the primary memory. So,
it is used to synchronize with high-speed CPU and to improve its performance.
Cache memory can only be accessed by CPU. It can be a reserved part of the main
memory or a storage device outside the CPU. It holds the data and programs which are
frequently used by the CPU. So, it makes sure that the data is instantly available for CPU
whenever the CPU needs this data. In other words, if the CPU finds the required data or
instructions in the cache memory, it doesn't need to access the primary memory (RAM).
Thus, by acting as a buffer between RAM and CPU, it speeds up the system performance.
C. Primary Memory
Memory unit is a component of a computer system. It is used to store data,
instructions and information. It is also known as a main/primary/internal memory.
Computer memory is of two basic types – Primary memory(RAM and ROM) and
Secondary memory (hard drive, CD, etc). Random Access Memory (RAM) is primary-
volatile memory and Read Only Memory (ROM) is primary-non-volatile memory.
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There are two types of Primary memory: –
1. Random Access Memory
RAM, which stands for Random Access Memory, is a hardware device generally located
on the motherboard of a computer and acts as an internal memory of the CPU. It allows
CPU store data, program, and program results when you switch on the computer. It is the
read and write memory of a computer, which means the information can be written to it as
well as read from it.
RAM is a volatile memory, which means it does not store data or instructions
permanently. When you switch on the computer the data and instructions from the hard
disk are stored in the RAM, e.g., when the computer is rebooted, and when you open a
program, the operating system (OS), and the program are loaded into RAM, generally from
an HDD or SSD. CPU utilizes this data to perform the required tasks. As soon as you shut
down the computer, the RAM loses the data. So, the data remains in the RAM as long as
the computer is on and lost when the computer is turned off. The benefit of loading data
into RAM is that reading data from the RAM is much faster than reading from the hard
drive.
In simple words, we can say that RAM is like a person's short term memory, and
hard drive storage is like a person's long term memory. Short term memory remembers the
things for a short duration, whereas long term memory remembers for a long duration.
Short term memory can be refreshed with information stored in the brains long term
memory. A computer also works like this; when the RAM fills up, the processor goes to
the hard disk to overlay the old data in Ram with new data. It is like a reusable scratch
paper on which you can write notes, numbers, etc., with a pencil. If you run out of space on
the paper, you may erase what you no longer need; RAM also behaves like this, the
unnecessary data on the RAM is deleted when it fills up, and it is replaced with new data
from the hard disk which is required for the current operations.
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RAM comes in the form of a chip that is individually mounted on the motherboard
or in the form of several chips on a small board connected to the motherboard. It is the
main memory of a computer. It is faster to write to and read from as compared to other
memories such as a hard disk drive (HDD), solid-state drive (SSD), optical drive, etc.
A computer's performance mainly depends on the size or storage capacity of the RAM. If it
does not have sufficient RAM (random access memory) to run the OS and software
programs, it will result in slower performance. So, the more RAM a computer has, the
faster it will work. Information stored in RAM is accessed randomly, not in a sequence as
on a CD or hard drive. So, its access time is much faster.
Functions of RAM are as follows:
It stores data till it gets processed.
It stores instructions for data processing.
It acts as a working space where data processing takes place and intermediate
results are stored.
It stores processed data/results before it is sent to output devices.
Types of RAM:
Integrated RAM chips can be of two types:
1. Static RAM (SRAM)
Data is stored in transistors and requires a constant power flow. Because of the
continuous power, SRAM doesn‟t need to be refreshed to remember the data being
stored. SRAM is called static as no change or action i.e. refreshing is not needed to
keep the data intact. It is used in cache memories.
Advantage: Low power consumption and faster access speeds.
Disadvantage: Less memory capacities and high costs of manufacturing.
2. Dynamic RAM (DRAM)
Data is stored in capacitors. Capacitors that store data in DRAM gradually discharge
energy, no energy means the data has been lost. So, a periodic refresh of power is
required in order to function. DRAM is called dynamic as constant change or action
i.e. refreshing is needed to keep the data intact. It is used to implement main
memory.
Advantage: Low costs of manufacturing and greater memory capacities.
Disadvantage: Slow access speed and high power consumption.
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2. Read Only Memory ROM
ROM, which stands for read only memory, is a memory device or storage medium
that stores information permanently. It is also the primary memory unit of a computer
along with the random access memory (RAM). It is called read only memory as we can
only read the programs and data stored on it but cannot write on it. It is restricted to
reading words that are permanently stored within the unit.
The manufacturer of ROM fills the programs into the ROM at the time of
manufacturing the ROM. After this, the content of the ROM can't be altered, which means
you can't reprogram, rewrite, or erase its content later. However, there are some types of
ROM where you can modify the data.
ROM contains special internal electronic fuses that can be programmed for a
specific interconnection pattern (information). The binary information stored in the chip is
specified by the designer and then embedded in the unit at the time of manufacturing to
form the required interconnection pattern (information). Once the pattern (information) is
established, it stays within the unit even when the power is turned off. So, it is a non-
volatile memory as it holds the information even when the power is turned off, or you shut
down your computer.
The information is added to a RAM in the form of bits by a process known as
programming the ROM as bits are stored in the hardware configuration of the device. So,
ROM is a Programmable Logic Device (PLD). A simple example of ROM is the cartridge
used in video game consoles that allows the system to run many games. The data which is
stored permanently on personal computers and other electronic devices like smartphones,
tablets, TV, AC, etc. is also an example of ROM.
For example, when you start your computer, the screen does not appear instantly. It takes
time to appear as there are startup instructions stored in ROM which are required to start
the computer during the booting process. The work of the booting process is to start the
computer. It loads the operating system into the main memory (RAM) installed on your
computer. The BIOS program, which is also present in the computer memory (ROM) is
used by the microprocessor of the computer to start the computer during the booting
process. It allows you to open the computer and connects the computer with the operating
system.
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ROM is also used to store Firmware, which is a software program which remains attached
to the hardware or programmed on a hardware device like a keyboard, hard drive, video
cards, etc. It is stored in the flash ROM of a hardware device. It provides instructions to the
device to communicate and interact with other devices.
Types of Rom
1. Programmable Read Only Memory (PROM)
PROM is a blank version of ROM. It is manufactured as blank memory and programmed
after manufacturing. We can say that it is kept blank at the time of manufacturing. You can
purchase and then program it once using a special tool called a programmer.
Uses: It is used in cell phones, video game consoles, medical devices, RFID tags, and
more.
2. Erasable and Programmable Read Only Memory (EPROM)
EPROM is a type of ROM that can be reprogramed and erased many times.
Uses: EPROM is used widely in personal computers. Since EPROM chips do not require
power to retain their data, they are commonly used to store BIOS information and basic
software for modems, video cards, and other peripherals.
3. Electrically Erasable and Programmable Read Only Memory (EEPROM)
ROM is a type of read only memory that can be erased and reprogrammed repeatedly, up
to 10000 times. It is also known as Flash EEPROM as it is similar to flash memory.
Uses: The BIOS of a computer is stored in this memory.
Sr.No RAM ROM
1 It is volatile memory. It is non-volatile memory.
2 The contents are temporary; data is
lost when electricity supply is lost.
The contents are permanent; data is not lost
even when power is switched off.
3 Available in small storage capacity. Available in high storage capacity.
4 Processing speed is high. Processing speed is low.
5 User-defined programs can be
stored.
Generally, operating system supporting
programs can be stored.
6 Cost is very high. Cost effective.
7 It is of two types, SRAM and
DRAM.
It comes in different types such as PROM,
EPROM.
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D. Secondary Memory
The secondary storage devices which are built into the computer or connected to the
computer are known as a secondary memory of the computer. It is also known as external
memory or auxiliary storage.
The secondary memory is accessed indirectly via input/output operations. It is non-volatile,
so permanently stores the data even when the computer is turned off or until this data is
overwritten or deleted. The CPU can't directly access the secondary memory. First, the
secondary memory data is transferred to primary memory then the CPU can access it.
Some of the secondary memory or storage devices are described below:
1- Hard Disk:
It is a rigid magnetic disc that is used to store data. It permanently stores data and is
located within a drive unit.
The hard disk is also known as a hard drive. It is a rigid magnetic disc that stores data
permanently, as it is a non-volatile storage device. The hard disk is located within a drive
unit on the computer's motherboard and comprises one or more platters packed in an air-
sealed casing. The data is written on the platters by moving a magnetic head over the
platters as they spin. The data stored on a computer's hard drive generally includes the
operating system, installed software, and the user's files and programs, including pictures,
music, videos, text documents, etc.
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2- Solid-state Drive:
SSD (Solid State Drive) is also a non-volatile storage medium that is used to hold
and access data. Unlike a hard drive, it does not have moving components, so it offers
many advantages over SSD, such as faster access time, noiseless operation, less power
consumption, and more. As the cost of SSD has come down, it has become an ideal
replacement for a standard hard drive in desktop and laptop computers. It is also suitable
for notebooks, and tablets that don't require lots of storage.
3- USB flash drive (pen drive):
USB flash drive is a compact secondary storage device. It connects to a computer
via a USB port. It is commonly used to store and transfer data between computers. For
example, you can write a report using a computer and then copy or transfer it in the USB
flash drive. Later, you can connect this USB flash drive to a computer to see or edit your
report. You can also store your important documents and pictures, music, videos in the
USB flash drive and keep it at a safe place.
USB flash drive does not have movable parts; it comprises an integrated circuit
memory chip that stores the data. This chip is housed inside a plastic or aluminum casing.
The data storage capacity of the USB flash drive generally ranges from 2 GB to 1 TB.
Furthermore, it is a plug and play device as you don't need additional drives, software, or
hardware to use it.
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4- SD Card:
SD Card stands for Secure Digital Card. It is most often used in portable and mobile
devices such as smartphones and digital cameras. You can remove it from your device and
see the things stored in it using a computer with a card reader.
There are many memory chips inside the SD card that store the data; it does not have
moving parts. SD cards are not created equal, so they may differ from each other in terms
of speed, physical sizes, and capacity. For example, standard SD cards, mini SD cards, and
micro SD cards.
5- Compact Disk (CD):
Compact Disk is a portable secondary storage device in the shape of a round medium
disk. It is made of polycarbonate plastic. The concept of CD was co-developed by Philips
and Sony in 1982. The first CD was created on 17 August 1982 at the workshop of Philips
in Germany.
In the beginning, it was used for storing and playing sound recordings, later it was used for
various purposes such as for storing documents, audio files, videos, and other data like
software programs in a CD.
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How Does a CD Work?
The data or information is stored or recorded or encoded in CD digitally using a laser
beam that etches tiny indentations or bumps on its surface. The bump is called a pit, which
represents the number 0. Space, where the bump is not created, is called land, and it
represents the number 1. Thus, the data is encoded into a compact disc by creating pits (0)
and lands (1). The CD players use laser technology to read the optically recorded data.
6- DVD:
DVD is short for digital versatile disc or digital video disc. It is a type of optical media
used for storing optical data. Although it has the same size as a CD, its storage capacity is
much more than a CD. So, it is widely used for storing and viewing movies and to
distribute software programs as they are too large to fit on a CD. DVD was co-developed
by Sony, Panasonic, Philips, and Toshiba in 1995.
Types of DVDs:
DVDs can be divided into three main categories which are as follows:
o DVD-ROM (Read-Only): These types of DVDs come with media already
recorded on them, such as movie dvds. As the name suggests, data on these discs
cannot be erased or added, so these discs are known as a read-only or non-writable
DVD.
o DVD-R (Writable): It allows you to record or write information to the DVD.
However, you can write information only once as it becomes a read-only DVD
once it is full.
o DVD-RW (Rewritable or Erasable): This type of discs can be erased, written, or
recorded multiple times.
Briefly, There are primarily three types of optical storage devices, CD (compact disk),
DVD (digital video disk) and BD (blue ray disk). CDs can hold about 700 MB data DVD
can hold about 4.7 GB data and Blue ray disk can have 5 times the storage of DVD. Solid
state storage devices are becoming more and more popular and they are replacing disk
drives (both magnetic and optic). They require less energy and quieter.
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5.1.5 Other Components of Computer Hardware
1. Motherboard
The motherboard serves as a single platform to connect all of the parts of a
computer together. It connects the CPU, memory, hard drives, optical drives, video card,
sound card, and other ports and expansion cards directly or via cables. It can be
considered as the backbone of a computer.
The motherboard is mounted inside the case and is securely attached via small
screws through pre-drilled holes. Motherboard contains ports to connect all of the internal
components. It provides a single socket for CPU, whereas for memory, normally one or
more slots are available. Motherboards provide ports to attach the floppy drive, hard
drive, and optical drives via ribbon cables. Motherboard carries fans and a special port
designed for power supply.
There is a peripheral card slot in front of the motherboard using which video cards,
sound cards, and other expansion cards can be connected to the motherboard.
On the left side, motherboards carry a number of ports to connect the monitor, printer,
mouse, keyboard, speaker, and network cables. Motherboards also provide USB ports,
which allow compatible devices to be connected in plug-in/plug-out fashion. For example,
pen drive, digital cameras, etc.
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2. Graphics Card
A graphics card is a type of display adapter or video card installed within most
computing devices to display graphical data with high clarity, color, definition and overall
appearance. A graphics card provides high-quality visual display by processing and
executing graphical data using advanced graphical techniques, features and functions.
A graphics card is also known as a graphics adapter, graphics controller, graphics
accelerator card or graphics board.
Explains Graphics Card
A graphics card is primarily designed to remove the graphical processing tasks
from the processor or RAM. It includes a dedicated graphical processing unit (GPU) and a
dedicated RAM that help it to process graphical data quickly. Like most processors, a
graphics card also has a dedicated heat sink to keep the heat out of the GPU. A graphics
card enables the display of 3-D images, image rasterization, higher pixel ration, a broader
range of colors and more. Moreover, a graphics card includes various expansion ports such
as AGP, HDMI, TV and multiple monitor connectivity. A graphics card can be integrated
within the motherboard or be added on as an extension card.
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5.2 Computer - Software
Software is a set of programs, which is designed to perform a well-defined
function. A program is a sequence of instructions written to solve a particular problem.
There are two types of software: -
System Software
Application Software
5.2.1 System Software
The system software is a collection of programs designed to operate, control, and
extend the processing capabilities of the computer itself. System software is generally
prepared by the computer manufacturers. These software products comprise of programs
written in low-level languages, which interact with the hardware at a very basic level.
System software serves as the interface between the hardware and the end users.
Some examples of system software are Operating System, Compilers, Interpreter,
Assemblers, etc.
Operating System
An Operating System (OS) is the most important software that runs on a computer.
OS acts as an interface between the user and the computer hardware and controls the
execution of all kinds of programs which is performs all the basic tasks like file
management, memory management, process management, handling input and output, and
controlling peripheral devices such as disk drives and printers. It also allows you to
communicate with the computer without knowing how to speak the computer's language.
Without an operating system, a computer is useless.
The Operating System is a program with the following features −
An operating system is a program that acts as an interface between the software
and the computer hardware.
It is an integrated set of specialized programs used to manage overall resources and
operations of the computer.
It is a specialized software that controls and monitors the execution of all other
programs that reside in the computer, including application programs and other
system software.
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5.2.2 Application Software
Application software products are designed to satisfy a particular need of a
particular environment. All software applications prepared in the computer lab can come
under the category of Application software.
Application software may consist of a single program, such as Microsoft's notepad
for writing and editing a simple text. It may also consist of a collection of programs, often
called a software package, which work together to accomplish a task, such as a
spreadsheet package.
Figure 1: Application Software Location
Examples of Application software are the following: -
Payroll Software
Student Record Software
Inventory Management Software
Income Tax Software
Railways Reservation Software
Microsoft Office Suite Software
Microsoft Word
Microsoft Excel
Microsoft PowerPoint
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Features of application software are as follows: -
Close to the user
Easy to design
More interactive
Generally written in high-level language
Easy to understand
Easy to manipulate and use
Sr.No. Software Hardware
1 It is a collection of programs to
bring computer hardware system
into operation.
It includes physical components of
computer system.
2 It includes numbers, alphabets,
alphanumeric symbols, identifiers,
keywords, etc.
It consists of electronic components like
ICs, diodes, registers, crystals, boards,
insulators, etc.
3 Software products evolve by
adding new features to existing
programs to support hardware.
Hardware design is based on architectural
decisions to make it work over a range of
environmental conditions and time.
4 It will vary as per computer and
its built-in functions and
programming language.
It is mostly constructed for all types of
computer systems.
5 It is designed and developed by
experienced programmers in high-
level language.
The hardware can understand only low-
level language or machine language.
6 It is represented in any high-level
language such as BASIC,
COBOL, C, C++, JAVA, etc.
The hardware works only on binary
codes 1‟s and 0‟s.
7 The software is categorized as
operating system, utilities,
language processor, application
software, etc.
The hardware consists of input devices,
output devices, memory, etc.
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6. Computer Numbering Systems
The language we use to communicate with each other is comprised of words and
characters. We understand numbers, characters and words. But this type of data is not
suitable for computers. Computers only understand the numbers.
So, when we enter data, the data is converted into electronic pulse. Each pulse is identified
as code and the code is converted into numeric format by ASCII. It gives each number,
character and symbol a numeric value (number) that a computer understands. So to
understand the language of computers, one must be familiar with the number systems.
The Number Systems used in computers are:
Binary number system
Decimal number system
Octal number system
Hexadecimal (hex) number system
1. Binary Number System
Binary Number System is a number system in which we represent the numbers by
using only two symbols i.e. 0 or 1. The binary system is applied internally by almost all
latest computers and computer-based devices because of its direct implementation in
electronic circuits using logic gates. Every digit is referred to as a bit.
Example
Binary Number: 101012
Calculating Decimal Equivalent:
Step Binary Number Decimal Number
Step 1 101012 ((1 x 24) + (0 x 2
3) + (1 x 2
2) + (0 x 2
1) + (1 x 2
0))10
Step 2 101012 (16 + 0 + 4 + 0 + 1)10
Step 3 101012 2110
Note − 101012 is normally written as 10101.
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2. Decimal Number System
In decimal number system we have 10 digits – 0 to 9 to represent the numbers.
Hence, the base value of the Decimal Number system is 10. Decimal number system is
used when there are 10 possible outputs of a system. For example, top 10 students from a
class. The number system that we use in our day-to-day life is the decimal number system.
Decimal number system has base 10 as it uses 10 digits from 0 to 9. In decimal number
system, the successive positions to the left of the decimal point represent units, tens,
hundreds, thousands, and so on.
Each position represents a specific power of the base (10). For example, the
decimal number 1234 consists of the digit 4 in the unit's position, 3 in the tens position, 2
in the hundreds position, and 1 in the thousands position. Its value can be written as
(1 x 1000) + (2 x 100) + (3 x 10) + (4 x l)
(1 x 103) + (2 x 102) + (3 x 101) + (4 x l00)
1000 + 200 + 30 + 4
Decimal to Binary and Binary to Decimal Number System Let us convert decimal number (87)10 to binary number.
Reminder Decimal
Number Base of Binary
1 87 2
1 43 2
1 21 2
0 10 2
1 5 2
0 2 2
1 1 2
So, in the above example. We first identified 2 is the base of the binary (target number
system). Then, we divided the given decimal number (87) with the base 2. And then we
noted the remainder in every step. And finally, we reversed the remainder and got the
answer –
(1010111)2.
Let us convert binary number (1011001)2 to decimal number.
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3. Octal Number System
Characteristics of the octal number system are as follows −
Uses eight digits, 0,1,2,3,4,5,6,7
Also called as base 8 number system
Example
Octal Number: 125708
Calculating Decimal Equivalent:
Step Octal Number Decimal Number
Step 1 125708 ((1 x 84) + (2 x 8
3) + (5 x 8
2) + (7 x 8
1) + (0 x 8
0))10
Step 2 125708 (4096 + 1024 + 320 + 56 + 0)10
Step 3 125708 549610
Note − 125708 is normally written as 12570.
4. Hexadecimal Number System
Characteristics of hexadecimal number system are as follows −
Uses 10 digits and 6 letters, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, A, B, C, D, E, F
Letters represent the numbers starting from 10. A = 10. B = 11, C = 12, D = 13, E =
14, F = 15
Also called as base 16 number system
Each position in a hexadecimal number represents a 0 power of the base (16).
Example, 160
Last position in a hexadecimal number represents a x power of the base (16).
Example 16x where x represents the last position – 1
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Example
Hexadecimal Number: 19FDE16
Calculating Decimal Equivalent: -
Step Binary
Number Decimal Number
Step 1 19FDE16 ((1 x 164) + (9 x 16
3) + (F x 16
2) + (D x 16
1) + (E x 16
0))10
Step 2 19FDE16 ((1 x 164) + (9 x 16
3) + (15 x 16
2) + (13 x 16
1) + (14 x 16
0))10
Step 3 19FDE16 (65536+ 36864 + 3840 + 208 + 14)10
Step 4 19FDE16 10646210
Note − 19FDE16 is normally written as 19FDE.
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7. Programming Languages
A program is a set of instructions that help computer to perform tasks. This set of
instructions is also called as scripts. Programs are executed by processor whereas scripts
are interpreted. The languages that are used to write a program or set of instructions are
called "Programming languages". Programming languages are broadly categorized into
three types −
Machine level language
Assembly level language
High-level language
1. Machine Level Language
Machine language is lowest level of programming language. It handles binary data
i.e., 0’s and 1’s. It directly interacts with system. Machine language is difficult for human
beings to understand as it comprises combination of 0‟s and 1‟s. There is software which
translate programs into machine level language. Examples include operating systems like
Linux, UNIX, Windows, etc. In this language, there is no need of compilers and
interpreters for conversion and hence the time consumption is less. However, it is non-
readable to humans.
2. Assembly Level Language
Assembly language is a middle-level language. It consists of a set of instructions in
a specific format called commands. It uses symbols to represent field of instructions. It is
very close to machine level language. The computer should have assembler to translate
assembly level program to machine level program. Examples include ADA, PASCAL,
etc. It is in human-readable format and takes lesser time to write a program and debug it.
However, it is a machine dependent language.
Assembly Language Machine Code
SUB AX, BX 0010101110000011
MOV CX, AX 100010111001000
MOV DX, 0 10111010000000000000000
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3. High-level Language
High-level language uses format or language that is most familiar to users. The
instructions in this language are called codes or scripts. The computer needs a compiler
and interpreter to convert high-level language program to machine level language.
Examples include C++, Python, Java, etc. It is easy to write a program using high level
language and is less time-consuming. Debugging is also easy and is a human-readable
language. Main disadvantages of this are that it takes lot of time for execution and
occupies more space when compared to Assembly- or Machine-level languages.
Following is a simple example for a high-level language.
if age < 18 {
printf("You are not eligible to vote");
} else {
printf("You are eligible to vote");
}
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8. Information Technology
Information technology (IT) is the use of any computers, storage, networking and
other physical devices, infrastructure and processes to create, process, store, secure and
exchange all forms of electronic data. Typically, IT is used in the context of enterprise
operations as opposed to personal or entertainment technologies. The commercial use of IT
encompasses both computer technology and telephony.
Information Technology (IT) is a business sector that deals with computing,
including hardware, software, telecommunications and generally anything involved in the
transmittal of information or the systems that facilitate communication. IT typically refers
to equipment such as computers, data storage devices, networks and also communication
devices. Information Technology means the use of hardware, software, services and
supporting infrastructure to manage and deliver information using voices, data and video.
Information Technology “IT” is one of the fastest growing industry in today‟s unstable
economy. Why? Because many businesses, Government organizations, Industries want to
automate their business and day-to-day processes.
1.2.1 Information Technology Examples
1. Software and support for office automation systems such as word processing and
spreadsheets, as well as the computer to run them.
2. Data networks and all associated communications equipment such as servers, bridges,
routers, hubs and wiring.
3. Peripherals directly connected to computer information systems used to collect or
transmit audio, video or graphic information, such as scanners and digitizers.
4. Voice response systems that interact with a computer database or application.
5. Video conferencing equipment.
6. The state radio communications network.
7. Computers and network systems used by teachers, trainers and students for educational
purpose.
8. “Open” computer systems that monitor or automate mechanical or chemical processes
and also store information used by computer applications for analysis and decision
making.
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1. Computer Network
Computer network is an interconnection between two or more hosts/computers.
The connectivity can be physical by using cables or virtual using wireless network.
Different types of networks include LAN, WAN, MAN, etc., as shown below:
Uses of Computer Network:
It allows you to share resources such as printers, scanners, etc.
You can share expensive software and database among network users.
It facilitates communications from one computer to another computer.
It allows the exchange of data and information among users through a network.
Popular Computer Networks:
Local Area Network (LAN)
Metropolitan Area Network (MAN)
Wide Area Network (WAN)
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1.1 Local Area Network (LAN)
As the name suggests, the local area network is a computer network that operates in
a small area, i.e., it connects computers in a small geographical area like within an office,
company, school, or any other organization. So, it exists within a specific area, e.g. home
network, office network, school network, etc.
A local area network may be a wired or wireless network or a combination of both.
The devices in a LAN are generally connected using an Ethernet cable, which offers an
interface to connect multiple devices like router, switches, and computers. For example,
using a single router, few Ethernet cables, and computers, you can create a LAN at your
home, office, etc. In this network, one computer may act as a server and other computers,
which are part of the network, may serve as clients.
Figure 2: Local Area Network
Topologies of LAN:
Topology: It refers to the arrangement of computers (nodes) in a computer network. The
main topologies of a local area network are as follows:
1. Ring Topology:
As the name suggests, in a ring topology, the computers are connected in a circular and
closed loop. The message in this topology moves only in one direction around the ring
from one node to another node and is checked by each node for a matching destination
address.
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2. Star Topology
In this topology, all the computers are separately connected to a central node or connection
point, which can be a server, a hub, a router, or a switch. This topology offers an advantage
that if a cable does not work, only the respective node will suffer, the rest of the nodes will
work smoothly. All data or messages that one node sends to another passes through the
central hub.
3. Bus Topology
In this arrangement, the nodes (computers) are connected through interface connectors to a
single communication line (central cable) that carries the message in both the directions.
Primary Functions of LAN:
o Sharing of files: It allows you to share or transfer files from one computer to
another computer within the LAN. For example, in a bank, it can be used to send a
file with the details of transactions of a customer from the server to clients.
o Sharing of printers: It also allows shared access to a printer, file servers, etc. For
example, ten computers that are connected through LAN can use a single printer,
file server, fax machine, etc.
o Sharing of Computational capabilities: It allows the clients to access to the
computational power of a server, e.g., an application server as some applications
which run on clients in a LAN may require higher computational capabilities.
o Mail and message related services: It allows sending and receiving mails between
computers of a LAN. You are required to have a mail server for this.
o Database services: It also allows storing and retrieving data with the help of a
database server.
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Benefits of LAN:
o It offers a higher operating speed than WAN and MAN.
o It is less expensive and easy to install and maintain.
o It perfectly fulfills the requirement of a specific organization, such as an office,
school, etc.
o It can be wired or wireless or a combination of both.
o It is more secure than other networks as it is a small set up that can be easily taken
care of.
1.2 Metropolitan Area Network (MAN)
MAN is a high-speed network that spreads over a large geographical area such as
a metro city or town. It is set up by connecting the local area networks using routers
and local telephone exchange lines. It can be operated by a private company, or it may
be a service provided by a company such as a local telephone company.
MAN is ideal for the people of a relatively large area who want to share data or
information. It provides fast communication via high-speed carriers or transmission
media such as copper, fiber optics, and microwaves. The commonly used protocols for
MAN are X.25, Frame Relay, Asynchronous Transfer Mode (ATM), xDSL (Digital
Subscriber Line), ISDN (Integrated Services Digital Network), ADSL (Asymmetrical
Digital Subscriber Line), and more.
The area covered by MAN is larger than the LAN but smaller than a WAN. Its network
ranges from 5 to 50 km. Furthermore, it also provides uplinks for connecting LANs to
WANs and the internet. An organization can use a MAN to connect all of its LANs
located at its different offices across the city.
Figure 3: Wide Area Network
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Advantages of MAN:
o Less Expensive: It is less expensive to set up a MAN and to connect it to a WAN.
o High Speed: The speed of data transfer is more than WAN.
o Local Emails: It can send local emails fast.
o Access to the Internet: It allows you to share your internet connection, and thus
multiple users can have access to high-speed internet.
o Easy to set up: You can easily set up a MAN by connecting multiple LANs.
o High Security: It is more secure than WAN.
1.3 Wide Area Network (WAN):
WAN extends over a large geographical area. It is not confined within an office,
school, city, or town and is mainly set up by telephone lines, fiber optic, or satellite
links. It is mostly used by big organizations like banks and multinational companies to
communicate with their branches and customers across the world. Although it is
structurally similar to MAN, it is different from MAN in terms of its range, e.g., MAN
covers up to 50 Kms, whereas WAM covers distances larger than 50 Km, e.g., 1000km
or more.
A WAN works by using TCP/IP protocol in combination with networking devices such
as switches, routers, firewalls, and modems. It does not connect individual computers;
rather, they are designed to link small networks like LANs and MANs to create a large
network. The internet is considered the largest WAN in the world as it connects various
LANs and MANs through ISPs.
The computers are connected to the wide area network through public networks, such
as telephone systems, leased lines or satellites. The users of a WAN do not own the
network as it is a large setup connecting the remote computer systems. However, they
are required to subscribe to a service provided by a telecommunication provider to use
this network.
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2. Internet
Internet is a global communication system that links together thousands of
individual networks. It allows exchange of information between two or more computers on
a network. Thus, internet helps in transfer of messages through mail, chat, video and audio
conference, etc. It has become mandatory for day-to-day activities: bills payment, online
shopping and surfing, tutoring, working, communicating with peers, etc.
It uses standard internet protocol suite (TCP/IP) to connect billions of computer
users worldwide. Protocol used is TCP/IP. This protocol connects any two networks that
differ in hardware, software and design. TCP/IP provides end to end transmission, i.e.,
each and every node on one network has the ability to communicate with any other node
on the network. It is set up by using cables such as optical fibers and other wireless and
networking technologies. At present, internet is the fastest mean of sending or exchanging
information and data between computers across the world.
Why is the Internet Called a Network?
Internet is called a network as it creates a network by connecting computers and
servers across the world using routers, switches and telephone lines, and other
communication devices and channels. So, it can be considered a global network of physical
cables such as copper telephone wires, fiber optic cables, tv cables, etc. Furthermore, even
wireless connections like 3G, 4G, or Wi-Fi make use of these cables to access the Internet.
Internet is different from the World Wide Web as the World Wide Web is a
network of computers and servers created by connecting them through the internet. So, the
internet is the backbone of the web as it provides the technical infrastructure to establish
the WWW and acts as a medium to transmit information from one computer to another
computer. It uses web browsers to display the information on the client, which it fetches
from web servers.
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Advantages of the Internet:
Instant Messaging: You can send messages or communicate to anyone using
internet, such as email, voice chat, video conferencing, etc.
Get directions: Using GPS technology, you can get directions to almost every
place in a city, country, etc. You can find restaurants, malls, or any other service
near your location.
Online Shopping: It allows you to shop online such as you can be clothes, shoes,
book movie tickets, railway tickets, flight tickets, and more.
Pay Bills: You can pay your bills online, such as electricity bills, gas bills, college
fees, etc.
Online Banking: It allows you to use internet banking in which you can check
your balance, receive or transfer money, get a statement, request cheque-book, etc.
Online Selling: You can sell your products or services online. It helps you reach
more customers and thus increases your sales and profit.
Work from Home: In case you need to work from home, you can do it using a
system with internet access. Today, many companies allow their employees to
work from home.
Entertainment: You can listen to online music, watch videos or movies, play
online games.
Cloud computing: It enables you to connect your computers and internet-enabled
devices to cloud services such as cloud storage, cloud computing, etc.
Career building: You can search for jobs online on different job portals and send
you CV through email if required.
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3. Web Browsing Software
"World Wide Web" or simple "Web" is the name given to all the resources of
internet. The special software or application program with which you can access web is
called "Web Browser".
Launching a Web Browser
Web browser is an application that is located on a computer‟s disk. Once you have an
internet connection, you can launch a web browser using the following methods −
Method 1
Step 1 − Go to "Start Menu".
Step 2 − From the menu opened, click on the web browser (Mozilla, Google Chrome,
Internet Explorer).
Method 2 − Alternate way is to click the shortcut icon on the taskbar or desktop.
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Popular Web Browsing Software
The most popular web browsing software includes:
1. Google Chrome
Google Chrome is a web browsing software developed in the year 2008 by Google
Inc. First, it was designed for windows platform, and later adopted to Linux, Macintosh,
and even Android. It is written using C++, Assembly, Python, and JavaScript.
2. Mozilla Firefox
Mozilla Firefox is a web browsing software developed in the year 2002 by the
Mozilla Foundation. It is designed to work on all operating systems like Windows,
Macintosh, Linux, and Android. It is written using C++, JavaScript, Rust, C, CSS, XUL,
and XBL.
3. Opera
Opera is a web browsing software developed in the year 1995 by Opera Software.
It is designed to work on all operating systems like Windows, Macintosh, and Linux and
is written using C++ language.
4. Internet Explorer
Internet Explorer is a web browsing software developed in the year 1995 by
Microsoft. It is designed to work on all operating systems like Windows, Macintosh,
Linux and Android and is written using C++ language.
Search Engines
Search Engine is an application that allows you to search for content on the web. It
displays multiple web pages based on the content or a word you have typed.
The most popular search engines are listed below.
1. Google
Google is the most popular and robust search engine launched in the year 1997 by
Google Inc. It was developed by Larry Page and Sergey Brin. It is written using C, C++
and Python. Beyond searching content, it also provides weather forecasts, sports score,
temperatures, area codes, language translation, synonyms, etc. Now-a-days the
advancement is still more, that it displays maps in a touch.
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2. Bing
Bing is also a popular search engine launched by Microsoft in the year 2009. It is
written using ASP .Net language. It is used to search web content, video, images, maps,
etc.
3. Yahoo
Yahoo is a common search engine launched by Yahoo in the year 1995. It is a
multilingual search engine and written using PHP language.
4. Ask
Ask is the most popular search engine and application for e-business which was launched
by IAO in the year 1996. It was developed by Garrett Gruener, David Warthen, and
Douglas Leeds.
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Search for The Content
Search Engine helps to search for content on web using the following steps.
Step 1 − Launch your web browser.
Step 2 − In "Address bar/Location", type the search engine you want to use and press
enter.
Step 3 − Type the content you want to search in the "search text box" and press enter.
Step 4 − It displays a list of web pages from which you can select corresponding
content/web page you want.
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4. E- Mail
Electronic mail (email or e-mail) is a method of exchanging messages ("mail")
between people using electronic devices. More plainly, e-mail is a message that may
contain text, files, images, or other attachments sent through a network to a specified
individual or group of individuals.
Email operates across computer networks, primarily the Internet. Today's email
systems are based on a store-and-forward model. Email servers accept, forward, deliver,
and store messages. Neither the users nor their computers are required to be online
simultaneously.
Email messages include three components, which are as follows:
o Message envelope: It depicts the email's electronic format.
o Message header: It contains email subject line and sender/recipient information.
o Message body: It comprises images, text, and other file attachments.
Advantages of Email
There are many advantages of email, which are as follows:
o Cost-effective: Email is a very cost-effective service to communicate with others
as there are several email services available to individuals and organizations for
free of cost. Once a user is online, it does not include any additional charge for the
services.
o Email offers users the benefit of accessing email from anywhere at any time if they
have an Internet connection.
o Email offers you an incurable communication process, which enables you to send a
response at a convenient time. Also, it offers users a better option to communicate
easily regardless of different schedules users.
o Speed and simplicity: Email can be composed very easily with the correct
information and contacts. Also, minimum lag time, it can be exchanged quickly.
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o Mass sending: You can send a message easily to large numbers of people through
email.
o Email exchanges can be saved for future retrieval, which allows users to keep
important conversations or confirmations in their records and can be searched and
retrieved when they needed quickly.
o Email provides a simple user interface and enables users to categorize and filter
their messages. This can help you recognize unwanted emails like junk and spam
mail. Also, users can find specific messages easily when they are needed.
o As compared to traditional posts, emails are delivered extremely fast.
o Email is beneficial for the planet, as it is paperless. It reduces the cost of paper and
helps to save the environment by reducing paper usage.
o It also offers a benefit to attaching the original message at the time you reply to an
email. This is beneficial when you get hundreds of emails a day, and the recipient
knows what you are talking about.
o Furthermore, emails are beneficial for advertising products. As email is a form of
communication, organizations or companies can interact with a lot of people and
inform them in a short time.
Gmail
Gmail is a free email service developed by Google. Users can access Gmail on the
web and using third-party programs that synchronize email content through POP or IMAP
protocols. Gmail started as a limited beta release on April 1, 2004 and ended its testing
phase on July 7, 2009.
At launch, Gmail had an initial storage capacity offer of one gigabyte per user, a
significantly higher amount than competitors offered at the time. Today, the service comes
with 15 gigabytes of storage. Users can receive emails up to 50 megabytes in size,
including attachments, while they can send emails up to 25 megabytes. In order to send
larger files, users can insert files from Google Drive into the message. Gmail has a search-
oriented interface and a "conversation view" similar to an Internet forum. By 2018, Gmail
had 1.5 billion active users worldwide.
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1. Computer Viruses
A computer virus is defined as a piece code or program which is executed in a
target computer to hamper the smooth functioning of the PC. It replicates itself and can
quickly affect hosts of other computers, thus paralyzing the entire network. So, it is
important for you to know how to remove it as soon as possible because a malware
infection can severely damage your data. It showed its existence in the year 1986 when the
first computer virus was created by the name of Brain for MS-DOS operating systems.
Mainly a boot sector Virus, it spreads through floppy disks. Nowadays, there are several
types of malicious software, which are developed using advanced coding technology.
Types of PC Virus
Although there are thousands of infectious programs that can affect your PC, these
are categorized on the basis of their infection targets.
1. Boot Sector Virus
Boot Sector Virus infects the Master Boot Record (MBR) of hard disks. Some virus
also infects the boot sector of hard drives. It spreads via external sources, for example, an
infected floppy disk or USB drive.
2. Macro Virus
A macro virus usually targets Microsoft Word, Microsoft Outlook, and similar
applications. The piece of the virus is embedded in documents or emails. And you
accidentally open the file, the virus gets activated and can spread to other files and folders.
3. Email Virus
Email Virus uses email medium to spread and infect PCs. These types of malware
come hidden in email attachments and execute as soon as you download or open the
attachment.
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How do Computer Viruses Spread?
A computer virus may spread if any external virus infected hard drive is inserted
into your PC. These removable devices can be a pen drive, an external hard disk or a
floppy drive. Apart from external hard drives, it spreads via email attachments, which can
easily carry malware. Your computer can also get infected if you download software,
movies, songs, etc. from untrusted websites.
Symptoms of Computer Virus Infection
You can easily identify the symptoms of computer virus infection. One major
indication is that your PC getting extremely slow. Another symptom can be your existing
firewall protection getting disabled. You will also experience frequent crashes of
applications running on your PC. Other alerts can be hard drive malfunction, error
messages & pop-ups.
How to Prevent Viruses?
In order to prevent viruses from infecting your computer, you must follow certain best
practices such as:
Do not insert removable devices/USB devices without scanning using a virus
scanner
Abstain from downloading software from untrusted websites
Don‟t open email attachments without verifying the sender id, content, and purpose
Use a premium antivirus software rather than free software as those may not be
capable of providing 100% protection.
How to Remove a Virus?
In order to eliminate the possibility of infection on your device, you need to first
delete all temporary files to speed up the virus scan process. Once you have deleted the
temp files, scan your PC using an antivirus software. You can use REVE Antivirus, which
scans computer threats using the turbo scan technology. This results in quick virus
detection and removal. After the removal of malicious code or infectious files from your
computer, always keep your antivirus software updated, so that any kind of latest threat can
be detected.
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Computer Crimes
Cybercrime, or computer-oriented crime, is a crime that involves a computer and a
network. The computer may have been used in the commission of a crime, or it may be the
target. Cybercrime may threaten a person, company or a nation's security and financial
health.
There are many privacy concerns surrounding cybercrime when confidential
information is intercepted or disclosed, lawfully or otherwise. Debarati Halder and K.
Jaishankar further define cybercrime from the perspective of gender and defined
'cybercrime against women' as "Crimes targeted against women with a motive to
intentionally harm the victim psychologically and physically, using modern
telecommunication networks such as internet and mobile phones". Internationally, both
governmental and non-state actors engage in cybercrimes, including espionage, financial
theft, and other cross-border crimes. Cybercrimes crossing international borders and
involving the actions of at least one nation-state is sometimes referred to as cyberwarfare.
Classifications of Computer crime
Computer crime encompasses a broad range of activities.
1. Financial fraud crimes
2. Cyberterrorism
3. Cyberextortion
4. Cybersex trafficking
5. Cyberwarfare
6. Computer as a target
7. Computer as a tool
8. Obscene or offensive content
9. Online harassment
10. Drug trafficking
Combating computer crime
1. Investigation
2. Prevention
3. Legislation
4. Awareness
5. Intelligence
CHAPTER 1
Getting Started with WindowsTo do something useful with your computer and with Windows 10, you need to learn a few basic tasks and techniques. These include exploring the screen, learning how to put your computer to sleep, how to restart and shut down your computer, how to connect to your network, and how to create a Microsoft account. You also need to learn how to work with apps, including installing them, starting them, and switching between them when you have multiple apps running. This chapter also shows you how to update and uninstall apps.
Explore the PC Screen . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4
Explore the Tablet Screen . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
Put Windows to Sleep . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6
Restart or Shut Down Windows . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
Connect to Your Wireless Network . . . . . . . . . . . . . . . . . . . . . . . . . .8
Switch to a Microsoft Account . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
Install an App . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14
Start an App . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16
Switch Between Running Apps . . . . . . . . . . . . . . . . . . . . . . . . . . . .18
Update an App . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20
Uninstall an App . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22
4
Before getting to the specifics of working with Windows 10, take a few seconds to familiarize yourself with the basic elements of the screen. These elements include the Start screen’s app tiles, live tiles, your user tile, and the Desktop tile.Understanding where these elements appear on the Start screen and what they are used for will help you
work through the rest of this book and will help you navigate Windows and its applications on your own. This section covers the screen you see on a PC. If you are using a Touch PC or a tablet, see the next section, “Explore the Tablet Screen.”
Explore the PC Screen
A Desktop IconAn icon on the desktop represents a program or Windows feature. A program you install often adds its own icon on the desktop.
C DesktopThis is the Windows “work area,” meaning that it is where you work with your programs and documents.
H Notification AreaThis area displays small icons that notify you about things that are happening on your computer. For example, you see notifications if your printer runs out of paper or if an update to Windows is available over the Internet.
I Time and DateThis is the current time and date on your computer. To see the full date, position the mouse ( ) over the time. To change the date or time, click the time.
B Mouse PointerWhen you move your mouse, this pointer moves along with it.
D Start ButtonYou use this button to start programs and launch many of Windows’ features.
E Search BoxYou use this box to search for items on your PC or on the Internet.
F Taskbar IconsYou use these icons to launch some Windows features with just a mouse click.
G TaskbarThe programs you have open appear in the taskbar. You use this area to switch between programs if you have more than one running at a time.
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1If you are using a touch‐based PC or a tablet device, Windows 10 will automatically reconfigure the screen into tablet mode, which is designed to make it easier for you to navigate and launch items using touches and other gestures. However, you
might find that using this new interface is not easier at first. To get more out of this interface and to learn how to operate your Touch PC or tablet, you need to familiarize yourself with Windows 10’s tablet mode.
A Tablet mode displays the Start screen, which consists of tiles for several common apps.
B In an app, you can click Back ( ) to return to either the previous app screen or to the Start screen.
C To return directly to the Start screen, you can click Start ( ).
1 To see more commands, click Menu ( ).
Windows displays a menu of commands.
2 To hide the commands, click Menu ( ) again.
D To toggle tablet mode on and off, you can click Action Center ( ) and then click Tablet Mode.
Explore the Tablet Screen
Explore the Tablet Screen
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You can make your computer more energy efficient by putting Windows into sleep mode when you are not using the computer. Sleep mode means that your computer is in a temporary low‐power mode. This saves electricity when your computer is plugged in, and it saves battery power when your computer is unplugged.
In sleep mode, Windows keeps your apps open. This is handy because it means that when you return from sleep mode, after you sign in to Windows again, you can immediately get back to what you were doing.
1 Click Start ( ).
The Start menu appears.
2 Click Power ( ).
3 Click Sleep.
Windows activates sleep mode.
Note: To return from sleep mode, press your computer’s Power button.
Put Windows to Sleep
Put Windows to Sleep
2
3
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1Restart or Shut Down Windows
1 Shut down all your running programs.
Note: Be sure to save your work as you close your programs.
2 Click Start ( ).
The Start menu appears.
3 Click Power ( ).
4 Click a command:
A Click Restart to shut down and then start your computer.
B Click Shut Down to turn off your computer.
You can restart Windows, which means that it shuts down and starts up again immediately. This is useful if your computer is running slowly or acting funny. Sometimes a restart solves the problem.Alternatively, when you complete your work, you could shut down Windows. However, do not just shut off your computer’s power because doing so can
cause problems: If you have documents with unsaved changes, you may lose those changes; you also could damage one or more Windows system files, which could make your system unstable. Therefore, you should always follow the proper steps when shutting down your PC.
Restart or Shut Down Windows
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A Windows displays a list of wireless networks in your area.
2 Click your network.
3 To have Windows connect to your network automatically in the future, click Connect automatically ( changes to ).
4 Click Connect.
1 Click Network ( ).
Connect to Your Wireless Network
If you have a wireless access point and your computer has built‐in wireless networking capabilities, you can connect to the wireless access point to access your network. If your wireless access point is connected to the Internet, then connecting to the wireless network gives your computer Internet access, as well.
Most wireless networks are protected with a security key, which is a kind of password. You need to know the key before attempting to connect. However, after you have connected to the network once, Windows remembers the password and connects again automatically whenever the network comes within range.
Connect to Your Wireless Network
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Windows asks if it can locate the other computers and devices on your network.
7 Click Yes.
Windows connects to the network.
C The network icon changes from Disconnected ( ) to Connected ( ) to indicate that you now have a wireless network connection.
If the network is protected by a security key, Windows prompts you to enter it.
5 Type the security key.
B If you want to be certain that you typed the security key correctly, temporarily click and hold Display Password Characters ( ).
6 Click Next.
How do I disconnect from my wireless network?To disconnect from the network, follow these steps:1 Click Network ( ).
2 Click your network.
3 Click Disconnect. Windows disconnects from the wireless network.si
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The Accounts window appears.
4 Click Sign in with a Microsoft account instead .
Start a Microsoft Account
1 Click Start (not shown).
2 Click Settings (not shown).
Windows opens the Settings app.
3 Click Accounts.
Switch to a Microsoft Account
You can get much more out of Windows by using a Microsoft account. When you connect a Microsoft account to your Windows user account, many previously inaccessible Windows features become immediately available. For example, you can use the Mail app to access your email and the OneDrive app
to store documents online. You can also download apps from the Windows Store, access your photos and documents anywhere online, and even sync your settings with other PCs for which you use the same account.
Switch to a Microsoft Account
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1The Make It Yours window appears.
Configure an Existing Microsoft Account
A To create a new Microsoft account, you can click Create one and then skip to the next subsection, “Configure a New Microsoft Account.”
1 Type your email address.
2 Type your password.
3 Click Sign in.
4 To finish configuring your existing account, skip to the subsection “Complete the Account.”
The Let’s Create Your Account window appears.
Configure a New Microsoft Account
1 Type your name.
2 Type the email address you want to use and select either outlook.com or hotmail.com from the list.
3 Type your password.
4 Select your country.
5 Type your date of birth.
6 Click Next.
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y it Can I use a new Microsoft email address?
Yes, you can. Windows does not require that you use an Outlook.com email address from Microsoft, but you can use such an address if you do not want to use an existing address. In the Let’s Create Your Account window, click the Get a new email address link and then type the username you want to use with Outlook.com. Your new address will be [email protected].
continued
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Complete the Account
Windows asks how you want to receive your security code to verify your account.
1 Click Next.
The Add Security Info window appears.
7 Select your phone number’s country code.
8 Type your mobile phone number.
9 Click Next.
Switch to a Microsoft Account (continued)
How you proceed after you type your email address depends on whether you are creating a new Microsoft account or using an existing account. Using a Microsoft account with Windows can help if you forget your account password and cannot log in.
You can provide Microsoft with your mobile phone number, so if you ever forget your password, Microsoft will send you a text message to help you reset your password. You can also give Microsoft an alternative email address, or you can provide the answer to a secret question.
Switch to a Microsoft Account (continued)
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Windows asks if you want to use a PIN with your account.
4 Click Skip this step.
Note: See the section “Set Up a Fingerprint Sign-In” in Chapter 11 to learn how to add a PIN to your account.
Windows connects the Microsoft account to your user account.
The next time you start Windows, you can use your Microsoft account email address and password to sign in.
Windows asks you to verify your current account password.
2 Type your password.
3 Click Next.
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y it If I no longer want to use a Microsoft account with Windows, can I remove it?Yes, you can revert to using your original user account at any time. Note, however, that you will no longer see any personal data on the Start screen, you will not be able to access your files online, and your settings will no longer sync between PCs. To remove the Microsoft account, click Start ( ), click your user name in the upper left corner, and then click Change account settings. In the Accounts window, click Sign in with a local account instead. Type your Microsoft account password, click Next, type your local account password (twice) and a password hint, and click Next. Click Sign out and finish to complete the removal.
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The Windows Store appears.
3 Use these tabs or the Search box to locate the app you want to install.
4 Click the app from the results that appear.
Install from the Windows Store
1 Click Start ( ).
2 Click Store.
A You might also be able to click the Store icon in the taskbar.
Note: You need a Microsoft account to install from the Windows Store, as described in the previous section, “Switch to a Microsoft Account.”
Install an App
If Windows does not come with an app that you need, you can obtain the app and then install it on your computer. How you start the installation process depends on whether you obtained the app from the Windows Store that comes with Windows
or you downloaded the app from the Internet. If you purchased the app from a retail store and received a physical copy of the software, you install the app using the CD or DVD disc that comes in the package.
Install an App
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15 Click Free.
If the app is not free, click the price button instead, type your Microsoft account password, and then click OK.
Windows installs the app.
Install a File Downloaded from the Internet
1 Click File Explorer ( ).
2 Click Downloads.
Note: If you saved the downloaded file in a folder other than Downloads, use File Explorer to find the downloaded file. To view a file with File Explorer, see Chapter 10.
The Downloads folder appears.
3 Double‐click the file.
The software’s installation app begins.
Note: For compressed files, extract the files and then double‐click the setup file. See Chapter 10 for more information.
4 Follow the installation instructions the app provides.
sim
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y it How do I find my software’s product key
or serial number?Look for a sticker attached to the back or inside of the CD case. Also look on the registration card, on the CD, or on the back of the box. If you downloaded the app, the number should appear on the download screen and on the email receipt you receive.
How do I install software from a CD or DVD?Insert the disc and, when the AutoPlay dialog box appears, click Run file, where file is the name of the installation app (usually SETUP.EXE). Then follow the installation instructions the app provides (these installation steps vary from app to app).
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The app runs.
D To close an app, you can click Close ( ) or press + .
Using the Start Menu
1 Click Start ( ).
A Your most frequently used apps appear here.
B Common Windows features appear here.
C The right side of the Start menu displays tiles for commonly used apps.
2 Click the app you want to start.
Start an App
To perform tasks of any kind in Windows, you can use one of the apps installed on your computer. The application you use depends on the task you want to perform. For example, if you want to surf the World Wide Web, you use a web browser application, such as the Microsoft Edge app that comes with Windows.
Before you can use an application, however, you must first tell Windows which application you want to run. You can start an app either from the Start menu or from the All Apps list.
Start an App
D
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E After you click All Apps, the name changes to Back.
3 Click the icon for the program you want to launch.
F If your program icon is in a submenu, click the submenu and then click the program icon.
Windows launches the app.
Using the All Apps List
1 Click Start ( ).
2 Click All apps.
sim
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y it What are tiles?
A tile is a method for displaying a shortcut that launches an app. Many tiles are live, which means that a tile’s text changes to display the app’s most recent information, such as the latest news or your most recently received email messages. See the section “Pin an App to the Start Menu” in Chapter 2 to learn how to add your own Start menu tiles.
Is there an easier way to locate an app?Yes, you can perform a search to locate it. Click inside the taskbar’s Search box and then begin typing the name of the app. As you type, Windows displays a list of apps and other items that match the characters. When you see the app you want, click it to run the program.
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B Windows brings the program’s window to the foreground.
Note: You can also switch to another window by clicking the window, even if it is in the background.
Switch Apps Using the Taskbar
1 Move the mouse ( ) over the taskbar button of the program you want to switch to.
A Windows displays a thumbnail version of the app window.
2 Click the app’s taskbar button.
Note: A program does not have to be minimized to the taskbar for you to use the program’s taskbar button.
Switch Between Running Apps
If you plan on running multiple applications at the same time, you need to know how to easily switch from one application to another. In Windows, after you start one application, you do not need to close that application before you open another one. Windows supports a feature called multitasking,
which means running two or more applications at once. For example, you might keep your word processing application, your web browser, and your email application open all day. You can switch from one program to another using either the taskbar or the keyboard.
Switch Between Running Apps
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C Windows displays thumbnails for each running program.
2 Click the thumbnail of the program you want to switch to.
Windows switches to the program.
Switch Apps Using Task View
1 In the taskbar, click Task View ( ).
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y it How can I switch between
apps using the keyboard?Press and hold and then press to see thumbnail versions of the open windows. Press until the window you want to work in is selected and then release .
Is there an easy way to arrange windows so they do not overlap?Yes, you can snap windows into place. To snap a window to the left half of the screen, drag the top of the window until the mouse ( ) hits the left edge of the screen, and then release. Similarly, drag a window to the right edge to snap it to the right. To snap a window to a quarter of the screen, drag the window to any corner.
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The Windows Store app appears.
A This number tells you how many updates are available.
3 Click Updates ( ).
1 Click Start ( ).
2 Click Store.
Update an App
You can ensure that you are using the latest version of an app by using the Windows Store to install an available update. After a software company releases an app, its programmers continue to work on it. They add new features, improve existing features, fix problems, and close security holes.
After fully testing these improvements and fixes, they place the new version of the app in the Windows Store, which alerts you that an update is available. You can then install the new version.
Update an App
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B If you prefer to update all the apps at once, click Update all and skip step 5.
5 Click Update ( ).
Windows installs the app updates.
The Windows Store displays a list of the available updates.
4 To ensure that you are seeing all the available updates, click Check for updates.
sim
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y it How do I update Windows?
By default, Windows is configured to automatically check for updated system files each day. If updates are available, Windows downloads and installs them. If you know of an important update, you can check for it manually if you would rather not wait for the automatic check. Click Start ( ) and then click Settings to open the Settings app. Click Update & security and then click Check for updates.
Can I automate the updates?Yes. Instead of updating your apps manually, configure Windows to update the apps automatically. In the Store app, click your user icon, click Settings, and then click the Update apps automatically switch to On.
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If you have an app that you no longer use, you can free up some hard drive space and reduce clutter on the Start screen by uninstalling that app. When you install an app, the program stores its files on your computer’s hard drive, and although most programs
are quite small, many require hundreds of megabytes of hard drive space. Uninstalling an app you do not need frees up the hard drive space it uses and removes its tile (or tiles) from the Start screen (if it has any there) and the Apps screen.
Uninstall an App
Windows asks you to confirm.
5 Click Uninstall.
Windows removes the app.
Uninstall via the Start Menu
1 Click Start ( ).
2 Use the Start menu or the All Apps list to locate the app you want to uninstall.
3 Right‐click the app.
4 Click Uninstall.
Uninstall an App
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1
The Programs and Features window appears.
3 Click the app you want to uninstall.
4 Click Uninstall (or Uninstall/Change).
The app’s uninstall procedure begins.
5 Follow the instructions on the screen, which vary from app to app.
Uninstall via Programs and Features
1 Type uninstall.
2 Click Change or remove a program.
sim
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Automatic and a Custom uninstall?The Automatic uninstall requires no input from you. It is the easiest, safest choice and therefore the one you should choose. The Custom uninstall gives you more control, but it is more complex and suitable only for experienced users.
How can I uninstall the app that is taking up the most space?Click Start ( ) and then click Settings to open the Settings app. Click System and then click Apps & features to see a list of apps sorted by size. To remove an app, click it, click Uninstall, and then click Uninstall when Windows asks you to confirm.
Working with FilesThis chapter shows you how to work with the files on your computer. These easy and efficient methods take you through all the basic file tasks, including how to view, select, copy, move, and rename files. You also learn how to delete files, as well as how to restore accidentally deleted files. This chapter also covers adding files to your online OneDrive, how to extract files from a compressed folder, and how to specify a different program when you open a file.
CHAPTER 10
Select a File . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .222
Change the File View . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .224
Preview a File . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .225
Copy a File . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .226
Move a File . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .227
Rename a File . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .228
Create a New File . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .229
Delete a File . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .230
Restore a Deleted File . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .231
Add a File to Your OneDrive . . . . . . . . . . . . . . . . . . . . . . . . . . . . .232
Extract Files from a Compressed Folder . . . . . . . . . . . . . . . . . . . .234
Specify a Different Program When Opening a File . . . . . . . . . . . . .236
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Select Multiple Files
1 Open the folder containing the files.
2 Click the first file you want to select.
3 Press and hold and click each of the other files you want to select.
Select a Single File
1 Click File Explorer ( ).
2 Open the folder containing the file.
3 Click the file.
Select a File
Before you can use File Explorer to do any work with one or more files, you first have to select the files so that Windows knows which ones you want to work with. For example, before you can move files to a new location, you must first select the files you want
to move. You can select just a single file, two or more files, or group of files, or all the files in a folder. Although you learn specifically about selecting files in this section, the technique for selecting folders is exactly the same.
Select a File
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Select All Files
1 Open the folder containing the files.
2 Click the Home tab.
3 Click Select all.
Note: A quick way to select all the files in a folder is to press
+ .
A File Explorer selects all the files in the folder.
Select a Group of Files
1 Open the folder containing the files.
2 Position the mouse ( ) slightly above and slightly to the left of the first file in the group.
3 Click and drag the mouse ( ) down and to the right until all the files in the group are selected.
sim
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y it How do I deselect a file?
Depending on the situation, there are a few ways to deselect files:
• To deselect a single file from a multiple‐file selection, press and hold and click the file you want to deselect.
• To deselect all files, either click the Home tab and then click Select none, or click an empty area within the folder.
• To reverse the selection — deselect the selected files and select the deselected files — click the Home tab and then click Invert selection.
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You can configure how Windows displays the files in a folder by changing the file view. This enables you to see larger or smaller icons or the details of each file.You can choose a view such as Small Icons to see more files in the folder window. A view such as Large
Icons or Extra Large Icons enables you to view images as thumbnail versions of each picture. If you want to see more information about the files, choose either the Tiles view or Details view.
1 In File Explorer, open the folder containing the files you want to view.
2 Click the View tab.
3 In the Layout section, click More ( ).
Windows displays the Layout gallery.
4 Click the view you want.
A File Explorer changes the file view (this example shows Tiles view).
Change the File View
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10Preview a File
1 In File Explorer, open the folder containing the file you want to preview.
2 Click the View tab.
3 Click Preview pane.
A The Preview pane appears.
4 Click a file.
B The file’s contents appear in the Preview pane.
C You can click and drag the left border of the Preview pane to change its size.
Note: When you are finished with the Preview pane, you can click Preview pane on the View tab to close it.
Windows enables you to view the contents of some files without opening them. This makes it easier to select the file you want to work with because it means you do not have to run an application to see
the file’s contents. Previewing the file is faster and uses fewer system resources. Windows previews only certain types of files, such as text documents, rich text documents, web pages, images, and videos.
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5 Open the location you want to use to store the copy.
6 Click the Home tab.
7 Click Paste.
A Windows inserts a copy of the file in the location.
1 In File Explorer, open the folder containing the file you want to copy.
2 Select the file.
3 Click the Home tab.
4 Click Copy.
Windows places a copy of the file in a special memory location called the Clipboard.
Copy a File
You can use Windows to make an exact copy of a file. This is useful if you want to back up an important file by making an extra copy on a flash drive, memory card, or other removable disc. Similarly, you might require a copy of a file if you want to send the
copy on a disc to another person. This section shows you how to copy a single file, but the steps also work if you select multiple files. You can also use these steps to copy a folder.
Copy a File
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10Move a File
1 In File Explorer, open the folder containing the file you want to move.
2 Select the file.
3 Click the Home tab.
4 Click Cut.
Windows places the file in the Clipboard.
5 Open the folder to which you want to move the file.
6 Click the Home tab.
7 Click Paste.
A Windows moves the file to the new location.
When you need to store a file in a new location, the easiest way is to move the file from its current folder to another folder on your computer. When you save a file for the first time, you specify a folder on your PC’s hard drive. This original location is not
permanent; you can move the file to another location on the hard drive. This section shows you how to move a single file, but the steps also work if you select multiple files or move a folder.
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1 In File Explorer, open the folder that contains the file you want to rename.
2 Click the file.
3 Click the Home tab.
Note: In addition to renaming files, you can also rename any folders that you have created.
4 Click Rename (or press ).
A text box appears around the filename.
Rename a File
You can change the name of a file, which is useful if the current name of the file does not accurately describe the file’s contents. By giving your document a descriptive name, you make it easier to find the file later.
Make sure that you rename only those documents that you have created or that someone else has given to you. Do not rename any of the Windows system files or any files associated with your programs, or your computer may behave erratically, or even crash.
Rename a File
5 Type the new name you want to use for the file.
Note: If you decide that you do not want to rename the file after all, press to cancel the operation.
Note: The name you type can be up to 255 characters long, but it cannot include the following characters: < > , ? : " \ *.
6 Press or click an empty section of the folder.
The new name appears under the file’s icon.
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10Create a New FileYou can quickly create a new file directly within a file folder. This method is faster, and often more convenient, than running a program’s New command. In Windows, you can create several different file types, such as a Bitmap Image (a drawing), Rich Text Document (a WordPad file), Text Document
(a Notepad file), and Compressed (Zipped) Folder (which combines multiple files in a single file, as described in the section “Extract Files from a Compressed Folder,” later in this chapter). You can also create a new folder.
1 In File Explorer, open the folder in which you want to create the file.
2 Click the Home tab.
3 Click New item.
4 Click the type of file you want to create.
A If you click Folder, Windows creates a new subfolder.
Note: The New Item menu on your system may contain more items than you see here because some programs install their own file types.
B An icon for the new file appears in the folder.
5 Type the name you want to use for the new file.
6 Press .
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1 In File Explorer, open the folder that contains the file you want to delete.
2 Click the file you want to delete.
Note: If you need to remove more than one file, select all the files you want to delete.
Note: See the section “Select a File,” earlier in this chapter, to select multiple files.
3 Click the Home tab.
4 Click the top half of Delete.
Note: Another way to select the Delete command is to press .
A Windows removes the file from the folder.
Note: Another way to delete a file is to click and drag it to the desktop Recycle Bin icon.
Delete a File
When you have a file that you no longer need, instead of leaving the file to clutter your hard drive, you can delete it. Make sure that you delete only those documents that you have created or that
someone else has given to you. Do not delete any of the Windows system files or any files associated with your programs, or your computer may behave erratically or crash.
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10Restore a Deleted FileIf you delete a file in error, Windows enables you to restore the file by placing it back in the folder from which you deleted it. You can restore a deleted file because Windows stores each deleted file in a
special folder called the Recycle Bin, where the file stays for a few days or a few weeks, depending on how often you empty the bin or how full the folder becomes.
1 Double‐click the desktop Recycle Bin icon.
Note: If you have a touch PC, open File Explorer, tap the first in the address bar, and then tap Recycle Bin.
Restore a Deleted File
The Recycle Bin folder appears.
2 Click the file you want to restore.
3 Click the Manage tab.
4 Click Restore the selected items.
The file disappears from the Recycle Bin and reappears in its original folder.
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Move a File to Your OneDrive
1 In File Explorer, open the folder that contains the file you want to move.
2 Click and drag the file to the OneDrive folder.
A As you drag, if you hover the file over OneDrive, File Explorer expands OneDrive to let you see your other OneDrive folders.
3 Drop the file on the OneDrive folder you want to use.
B File Explorer moves the file to the OneDrive folder.
Add a File to Your OneDrive
If you are using Windows under a Microsoft account, then as part of that account you get a free online storage area called OneDrive. You can use the special OneDrive folder on your PC to move or copy any of your files to your OneDrive. This is useful if you are
going to be away from your computer but still require access to a file. Because the OneDrive is accessible anywhere you have web access, you can view and work with your file without using your computer.
Add a File to Your OneDrive
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10Copy a File to Your OneDrive
1 In File Explorer, open the folder that contains the file you want to copy.
2 Press and hold and then click and drag the file to the OneDrive folder.
C If needed, hover the file over OneDrive to see your other OneDrive folders.
3 Drop the file on the OneDrive folder you want to use.
D File Explorer copies the file to the OneDrive folder.
sim
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Yes. As part of your OneDrive, Microsoft gives you access to the Office Web Apps, which are scaled‐down, online versions of the Microsoft Office applications. To create a document using one of these programs, navigate to your online OneDrive, click Create, and then click Word document, Excel workbook, PowerPoint presentation, OneNote notebook, Excel survey, or Plain text document.
How do I access my OneDrive online?You need to open Microsoft Edge and navigate to the OneDrive site, http://onedrive.live.com. After you are logged in to your OneDrive, you can use it to create new folders, rename files, delete files, and more.
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View Compressed Folder Files
1 In File Explorer, open the folder containing the compressed folder.
A The compressed folder usually appears as a folder icon with a zipper.
2 Double‐click the compressed folder.
Extract Files from a Compressed Folder
If someone sends you a file via email, or if you download a file from the Internet, the file often arrives in a compressed form, which means the file actually contains one or more files that have been compressed to save space. To use the files on your computer, you need to extract them from the compressed file.
Because a compressed file can contain one or more files, it acts like a kind of folder. Therefore, Windows calls such files compressed folders, zipped folders, or Zip archives. You can view these files or extract them from the folder.
Extract Files from a Compressed Folder
B File Explorer displays the contents of the compressed folder.
Note: File Explorer is only displaying the contents of a compressed folder; it has not extracted the files. To extract the files, follow the steps in the next subsection.
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The Select a Destination and Extract Files dialog box of the Extract Wizard appears.
5 Type the location of the folder into which you want to extract the files.
C You can also click Browse and choose the folder.
6 If you want to open the folder into which you extracted the files, click Show extracted files when complete ( changes to ).
7 Click Extract.
Windows extracts the files.
Extract Compressed Folder Files
1 In File Explorer, open the folder containing the compressed folder.
2 Click the compressed folder.
3 Click the Extract tab.
4 Click Extract all.
How can I create a compressed folder?Follow these steps:1 Select the files and folders you
want to store in the compressed folder.
2 Right‐click any selected item.
3 Click Send to.
4 Click Compressed (zipped) folder.
The compressed folder appears.
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Windows asks how you want to open this file type.
5 Click More apps.
1 In File Explorer, open the folder that contains the file you want to open.
2 Click the file.
3 Click the Open .
A If the program you want to use appears here, click the program and skip the remaining steps.
4 Click Choose another app.
Specify a Different Program When Opening a File
You can open a file in a different program from the one normally associated with the file. This enables you to use the other program’s features to work on the file.You may have situations where you prefer to open a particular file with a different program. For example,
double‐clicking a picture file opens it in the Photos app. However, you may prefer to open the picture file in Paint or some other image‐editing program so that you can make changes to the picture. This section shows you how to open any document in another program.
Specify a Different Program When Opening a File
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10 B Windows displays a full list of
programs you can use to open the file.
6 Click the program you want to use to open the file.
C If the program you want to use does not appear in the list, you can click Look for another app on this PC and use the Open With dialog box to specify the program.
7 Click OK.
Windows opens the file in the program you chose.
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y it Can I set the default program for multiple
file types?Yes. In the taskbar’s Search box, type set default, click Default Programs, and then click Set your default programs. Click the program you want to use, click Choose defaults for this program, click each file type you want to open with the program ( changes to ), and then click Save.
How can I open every file of the same type in the new program?If you want to open every file of the same type — such as Text Document files or Rich Text Format files — in the same program, follow steps 1 to 6 and then click Always use this app to open .ext files ( changes to ).