Week 1: Hardware & Software
Muhammad Shahzad Ali
LECTURE
1
Grade - 8
HARDWARE &
SOFTWARE
Orbit International School
Week 1: Hardware & Software
Muhammad Shahzad Ali
• All ICT systems consists of two main parts:
– Hardware
– Software
Grade - 8
Orbit International School
Week 1: Hardware & Software
Muhammad Shahzad Ali
Hardware
• Hardware means those parts of the computer you can
touch.
• This means that they are components such as;
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Printer
Keyboards
Memory
Storage devices etc.
• Even the storage media is classed as hardware.
Grade - 8
Orbit International School
Week 1: Hardware & Software
Muhammad Shahzad Ali
Software
• Software means the programs that supply the
instructions to the hardware to tell it what to do.
– “the actual programs consisting of instructions that
allow the hardware to do a useful job”.
• For example;
– Operating system
• MS Windows, Apple Mac, Red Hat etc.
– Application Software
• MS Word, MS Excel, MS PowerPoint etc.
Grade - 8
Orbit International School
Week 1: Hardware & Software
Muhammad Shahzad Ali
Examples of Computer Hardware
• Hardware consists of the physical components of an
ICT system.
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Grade - 8
Keyboard
Monitor
Processor
Speakers
Mouse
Fixed hard disks
ROM/RAM
Printer
Web cam
Orbit International School
Week 1: Hardware & Software
Grade - 8
Muhammad Shahzad Ali
Orbit International School
Week 1: Hardware & Software
Grade - 8
Muhammad Shahzad Ali
Orbit International School
Week 1: Hardware & Software
Grade - 8
Muhammad Shahzad Ali
Orbit International School
Week 1: Hardware & Software
Muhammad Shahzad Ali
Examples of Computer Software
• The software is the set of instructions that tells the
computer hardware what to do.
• Computer software is written in a computer language
and there are quite a few different ones.
• Computer hardware is useless without software.
• There are two main types:
– Operating Systems
– Applications Software
Grade - 8
Orbit International School
Week 1: Hardware & Software
Muhammad Shahzad Ali
Examples of Computer Software
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Grade - 8
Operating systems
Word-processing package
Presentation package
Spreadsheet package
Web browser
Database
CAD
Web design package
Photo editing package
Orbit International School
Week 1: Hardware & Software
Grade - 8
Muhammad Shahzad Ali
Orbit International School
Week 1: Hardware & Software
Grade - 8
Muhammad Shahzad Ali
Orbit International School
Week 1: Hardware & Software
Muhammad Shahzad Ali
Main components of General-Purpose Computer
Grade - 8
Orbit International School
Week 1: Hardware & Software
Muhammad Shahzad Ali
• The main components of a general-purpose computer
are:
– Input devices (keyboard, mouse, etc)
– Output devices (printer, monitor, speakers, etc)
– Secondary storage devices (DVD-R, Hard disks, etc)
– Processor and Internal memory devices
Grade - 8
Orbit International School
Week 1: Hardware & Software
Muhammad Shahzad Ali
• The Processor and Internal memory devices include
the;
– Central Processing Unit (CPU),
– Read Only Memory (ROM),
– Random Access Memory (RAM)
Grade - 8
Orbit International School
Week 1: Hardware & Software
Muhammad Shahzad Ali
Central Processing Unit (CPU)
• The CPU, often the Processor, is the brain of the
computer;
– and it consists of millions of tiny circuits on a silicon
chip.
Grade - 8
Orbit International School
Week 1: Hardware & Software
Grade - 8
Muhammad Shahzad Ali
Orbit International School
Week 1: Hardware & Software
Muhammad Shahzad Ali
• CPU functions:
– The CPU controls the step-by-step running of the
computer system
– It does all the calculations and
– Perform all the logical operations and
– Deals with the storage of data and programs in
memory.
Grade - 8
Orbit International School
Week 1: Hardware & Software
Muhammad Shahzad Ali
Internal Memory (ROM / RAM)
• There are two types of memory called ROM & RAM.
• Both these two types of memory are stored on chips
and are available immediately to the CPU.
• Memory (i.e. ROM & RAM) is often called primary
storage.
Grade - 8
Orbit International School
Week 1: Hardware & Software
Muhammad Shahzad Ali
ROM (Read Only Memory)
• ROM is the fast permanent memory used for holding
instructions needed to start up the computer.
• ROM is:
– Held on a computer chip.
– Called non-volatile memory because it does not lose
its contents when the power is turned off.
Grade - 8
Orbit International School
Week 1: Hardware & Software
Muhammad Shahzad Ali
– Used to hold instructions to start the computer, which
are called the boot program or BIOS (Basic Input/Out
System).
• It is the job BIOS to find out which devices are connected to
the computer when it is first switched on and also loads the
operating system.
– ROM is used to store data that cannot be altered by
the user.
Grade - 8
Orbit International School
Week 1: Hardware & Software
Grade - 8
Muhammad Shahzad Ali
Orbit International School
Week 1: Hardware & Software
Muhammad Shahzad Ali
RAM (Random Access Memory)
• RAM is a fast temporary memory where programs and
data are stored only when the power is supplied.
• RAM is:
– Held on a computer chip
– Called volatile memory because the contents
disappear when the power is turned off.
– Can be written to and read from
– Can be altered by the user
– Holds the software currently in use by the user
Grade - 8
Orbit International School
Week 1: Hardware & Software
Muhammad Shahzad Ali
RAM
Grade - 8
Orbit International School
Week 1: Hardware & Software
Muhammad Shahzad Ali
The Importance of ROM & RAM
• Having a large amount of ROM and RAM in a
computer is important, because having more memory
means:
– Applications run faster on their own
– More applications are able to run at the same time
– Users are able to move quickly between applications.
Grade - 8
Orbit International School
Week 1: Hardware & Software
Muhammad Shahzad Ali
Input devices
• These are used to get raw data into the computer ready
for processing by the CPU.
• Some input devices, such as a mouse, keyboard, touch
screen, microphone, etc are manual and need to be
operated by a human.
• Other are automatic and once they are set up they can
be left to input the data on their own.
– These include optical mark readers, optical character
readers, etc.
Grade - 8
Orbit International School
Week 1: Hardware & Software
Muhammad Shahzad Ali
Output devices
• Once the raw data has been processed it becomes
information and this information needs to be output
from the computer using an output device.
• Output devices include monitors/screens, printers,
speakers, plotters, etc.
Grade - 8
Orbit International School
Week 1: Hardware & Software
Muhammad Shahzad Ali
Backing Storage
• Secondary storage devices use removable media.
• Secondary/backing storage is used for the storage of
programs and data that are not needed instantly by the
computer.
• It is also used for long-term storage of programs and
data as well as for backup copies in case the original
data is lost.
Grade - 8
Orbit International School
Muhammad Shahzad Ali
Week 1: Hardware & Software
• Secondary/backing storage media includes
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Grade - 8
portable hard disks,
magnetic tape,
memory sticks,
flash memory cards, and
optical disks such as CD and DVD.
Orbit International School