The document discusses the different types of hardware and software components that make up a computer system. It describes input devices like keyboards and mice that allow users to input data. It covers output devices like monitors and printers that display or print the output. It also discusses the central processing unit and memory that process data in the system unit. Storage devices like hard drives, USBs and CDs are explained for permanent storage. Communication devices allow computers to connect and exchange information. The document ends by distinguishing system software, like operating systems, from application software used by users to perform tasks.

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Hardware:
The Physical parts of the computer are called hardware. The user can see and touch the hardware.
Different types of hardware components are as follows:
 Input devices such as Keyboard, mouse, joystick etc.
 The Central Processing Unit (CPU).
 Output devices such as printer, monitor etc.
 Storage devices such as disk drive, hard drive -
Components of Hardware:
Different components of computer system are as follows:
 Input Devices:
The data and instructions given to the computer are called input. A hardware component used to
enter data and instructions into a computer is called input device. Input devices take data and
instructions from the user and convert it in a form that is understandable by the computer. Most
commonly used input devices are as follows:
 Keyboard:
Keyboard is the most commonly used input device. Data is mostly entered using a keyboard. The
buttons on the keyboard are called keys. A typical keyboard contains 101 to 105 keys. The
arrangement of keys on keyboard is called keyboard layout. The most popular keyboard layout is
QWERTY.
Keyboard is used to type following:
Input devices Output devices System unit
Storage devices
Communication
devices

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 Alphabets(A to Z and a ton z),
 Numbers (0 to 9),
 Spaces
 Symbols like %, $, and # etc.
 Mouse:
Mouse is the most widely used pointing device on desktop computers. It is used to input instructions
with a pointer on the screen. Mouse is moved on a flat surface to control the movement of cursor or
pointer on the screen. The mouse is attached to the computer by a cable or wireless connection. A
mouse is mostly used in graphic applications. A mouse usually has two or three buttons. These
buttons are used to selecting an object or operating a program.
 Microphone:
A microphone is an input device. It is used to digitally record audio data like such as human voice.
It can be plugged in to a computer or recorder. Many software applications can accept data with
microphone. It enables a user to input text and issue commands orally. The software in the computer
converts the sound waves into digital form. It is then stored in memory and used according to the
requirement.
 Digital Scanner :
Digital scanner is an input device. It is used to read the pictures and other printed materials placed
on its glass. It reads the picture, translates it in digital form and stores it in the computer. Digital
scanner uses laser technology to read images.
 Digital camera:
Digital camera is an input device. It stores images digitally in its memory rather than recording on
film. The pictures taken with a digital camera can be transferred to a computer system. Many digital
cameras allow the user to edit images. Digital camera makes photos inexpensive and fast. Most
digital cameras store images in internal flash memory.
 PC Camera:
PC camera is used to create movie and take photos on the computer. It is also used to make a video
phone call.
 Output Devices:
The data has been processed into useful information is called output. Hardware components are
used to receive information from the computer is called output devices. Output devices take

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information from the computer and convert it in a form that is understandable by the users. Soma
important output devices are as follows:
 Monitors:
Monitor is the most common output device. The output displayed by monitor is called soft copy. A
monitor looks like a television and displays text and graphics. A monitor is also known as display
screen or simply screen.
 Printers:
A printer is an output device that prints characters, symbols and graphics on paper. Printers are used
in business to print the documents on paper. The printed output is called hard copy. Print resolution
is commonly measured in dots per inch (dpi).Printers with high dpi procedure higher quality output.
 Plotters:
A plotter is an output device that is used to produce high quality graphics in a variety of colors.
Plotters are used to create maps, architectural drawings, graphs and charts. A plotter works by
drawing lines on paper using pens held in a mechanical arm.
 Speakers:
A type of output produced in the form of sound, voice or music is known as audio output. Speaker
is commonly used audio output device. Many personal computers have internal speaker. The quality
of internal computer is not very high. Some monitors also contain speaker on their sides.
 Data Projectors:
Data projector is an output device that projects the output of computer screen into a large screen.
The output projected by data projector can be viewed by a large number of people very clearly. Data
projectors are used in classes to deliver lectures to many students.
Difference between Input and Output devices:
Input Devices Output Devices
1. Input devices give data and instructions
to the computer.
1. Output devices take information from
the computer.
2. Input devices take data and instructions
from the user and convert it in a form that
is understandable by the computer.
2. Output devices take information from
the computer and convert it in a form that
is understandable by the users.

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3. Examples of input devices are keyboard
and mouse.
3. Examples of input devices are monitor
and printer.
 System Unit:
System unit is a box that contains different electronic components of computer used to process data.
All computer systems have a system unit. The electronic components in system unit are connected
to the motherboard. The motherboard is the communication medium for the entire computer system.
Two main components in system unit are as follow:
 CPU:
CPU stands for central processing unit. It is also called processor. It is the brain of the computer. It
is the most important component of a computer. It interprets and executes the instructions in
computer. A computer cannot work without CPU.
 Memory:
The hardware component that stores data and instructions temporarily is called memory. It consists
of electronic chips that connected to the motherboard. The main memory is also called volatile
memory because its contents are lost when the computer is turned off.
(Frinza Azhar 13023901-030)
 Storage Devices:
The devices used to store data and programs permanently are called storage devices. Storage
usually refers to the secondary storage. The main memory stores data and programs
temporarily. The secondary storage is required to store data, information and programs
temporarily. The most common storage devices are floppy disk, hard disk drive, CD-ROM
and USB etc.
Some storage devices are:
 Floppy Disk or Disk kittle:
Floppy disk is also called diskette. It consists of a thin disk plastic disk coated with magnetic
material. The disk is enclosed in a plastic jacket. It is a portable storage medium and can be
removed from one computer and inserted into another computer easily.
 HARD DISK OR DISKETTE:
Hard disk is a type of magnetic disk. It is also called fixed disk because it is fixed in the
system unit. The container contains a motor to rotate to disk. The platter is used to store
data. A platter in a hard disk is coated with a magnetic material.

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 CD-ROM:
CD-ROM stands for Compact DISK read-ONLY memory. It can store about 700 MB of
data. CD ROM drive is used to read data from CD_ROM.
 USB FLASH DRIVES:
USB flash drive is a memory storage device that is connected to a USB port in computer be
mobile device. It is also called thumb drive, key drives, or jump drives. USB flash drive is
very easy to use because it is light in weight and small in size. It can easily be placed in
pocket or attached to a keychain. It is available in different shapes, sizes and capacities. The
storage capacity of USB drive is from 512 MB to 100 GB.
 COMMUNICATIN DEVICES:
The hardware components used to communicate and exchange data, instructions and
information with other computers are called communication devices, and an important
communication device is called modem. It enables them to communication with other
computer via a telephone line or cable.
(Sidra shabbir 13023901-003)
Software:
A set of instruction given to the computer to solve a problem is called software. Software is also
called a program. Different software is used to solve different problems. A computer works
according to the instructions written in software.
Types of Software
System Software Application software
 System Software:
System software is set of program required to implement certain functions in a computer system. It
controls the operation of a computer system. It also controls the usage and allocation of difference
hardware component. It enables application programs to execute properly.

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Examples of System Software
Examples of system software are as follows:
 Operating System
 Utility Programs
 Device drivers
Type of System Software
 Operating System:
An Operating systemis a set of programs that manage all computers and operations. A computer
cannot do anything without operating system. Operating system must be installed on every
computer. Users interact with the computer through the operating system. Microsoft Windows and
Linux are examples of operating system software.
 Utility Programs:
A utility program is a type of system software that is used for effective management of computer
system. The user can use a utility program to perform maintenance tasks related to different devices
and programs. The utility programs keep the computer system running smoothly. Antivirus and file
compression software are examples of utility programs.
(Maryam Sultana 13023901-016)
Application Software:
Application software is used to perform various applications on the computer. It helps a
computer user to perform specific tasks. People use application software according to their needs.
For example, it provides audio, video and multimedia entertainment to the users. It is also known as
application package.
Categories of application software
The main categories of application software are as follows:
a) Customized Software:
Customized software is a type of application software that is designed for a particular customer or
organization. It is developed to meet the exact requirements of a particular customer or

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organization. The cost of customized software is more than packaged software.
Software that is developed for a particular university is an example of customized software.
The software can be developed by single programmer or a team of programmers.
b) Package Software:
Package software is a type of application software that is developed for sale to the general
public. It is also known as off-the-shelf software. It facilitates the people to perform day-to-day
activities. Package software is normally developed by expert programmers.
Examples of package software are as follows:
 Word processors
 Spreadsheet
 Database
 Graphics
 Communication software etc.
Differentiate between systemsoftware and application software
The difference between system and application software is as follow:
System Software Application Software
1) It is general-purpose software 1) It is specific purpose software.
2) It is used manage computer resources 2) It is used to solve particular
problems.
3) It executes all the time in computer. 3) It executes as and when required
4) The number of system software is less than
application software.
4) The number of application
software is much more than system
software.
5) System software is essential for a computer
to work
5) Application software is not
essential for a computer to work

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.
Difference between software and hardware
The difference between software and hardware is as follows:
Software Hardware
1. Software is a set of instructions
that tell a computer exactly what to do.
1. Hardware is physical parts of
computer that cause processing of data.
2. Software cannot be executed
without hardware.
2. Hardware cannot perform any task
without software
3. Software cannot be touched 3. Hardware can be seen and touched
4. Software is debugged in case of
problem.
4. Hardware is repaired in case of
problem
5. Software is reinstalled if the
problem is not saved.
5. Hardware is replaced if the
problem is not solved
(Rida Ijaz 13023901-041)
Reference:
Book name/computer applications in business
(Written by) Tasleem Mustafa, Tariq mahmood…