Hardware
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Hardware refers to the physical components of a computer system
These components can be internal or external
Internal Components
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Central Processing Unit (CPU): the computer's "brain" that performs calculations,
processes instructions, and controls other components
Processor: a chip inside the CPU that carries out instructions from a program
Motherboard: the main circuit board that connects all internal components
Internal Memory
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Random Access Memory (RAM): temporary storage for running programs and data; it
is volatile, meaning data is lost when the computer is turned off
Read-Only Memory (ROM): permanent storage for essential data, like the
computer's BIOS; it is non-volatile, meaning data is retained even when the computer is
turned off
Hardware Components
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Graphics card: processes images and videos for display on a monitor
Sound card: processes audio for output through speakers or headphones
Network Interface Card (NIC): enables connection to a network, such as the internet
Camera: captures images or video for input into the computer
Internal/external storage devices: stores data permanently, such as hard drives or
USB flash drives
Input devices: allow users to enter data, like keyboards and mice
Output devices: display or produce results, like monitors and printers
worked example
A computer contains internal hardware. Write down the most appropriate item of internal
hardware to match the descriptions.
a. This handles all the system instructions
[1]
Processor / CPU [1]
b. A printed circuit board that contains the main components of the computer
[1]
Motherboard [1]
c. This generates output for the speaker
[1]
Sound card [1]
d. A type of memory where data is lost when the computer is switched off
[1]
RAM / Random Access Memory [1]
Software
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Software refers to programs that control the operation of a computer or the processing
of electronic data
Application Software
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Application software provides the services that users require to solve a task
E.g.:
o Word processing: creating and editing text documents
o Spreadsheet: organising and analysing data in a grid format
o Database management systems: storing, retrieving and managing data in
databases
o Control/measurement: uses sensors to measure and control a system
o Applets and apps: specialised software for specific tasks
o Video editing: creating and modifying video files
o Graphics editing: creating and modifying images
o Audio editing: creating and modifying sound files
o Computer Aided Design (CAD): designing and modelling objects in 2D or 3D
System Software
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System software provides the services that the computer requires to operate e.g.
o Compilers: translating high-level programming languages into machine code
o Linkers: combining object files into a single executable program
o Device drivers: controlling hardware components and peripherals
o Operating systems: managing the computer's resources and providing a user
interface
o Utilities: tools for maintaining and optimising the computer's performance
worked example
Tick whether the following are examples of applications software or system software
Applica ons
So ware
(✓)
Control so ware
✓
✓
Compiler
Word processing
Device drivers
System
So ware
(✓)
✓
✓
2 marks for 4 correct ticks
1 mark for 2 or 3 correct ticks
0 marks for 0 or 1 tick
exam tIp
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A common misconcep on is that control so ware is system so ware - it's actually applica on
so ware
operatIng SyStemS
An Operating System has a user interface to allow the user to interact with the computer. There
are different types of user interfaces:
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Command Line Interface (CLI)
o Text-based interface
o Users type commands to perform tasks
o Requires knowledge of command syntax
Graphical User Interface (GUI)
o Visual-based interface with icons, windows, and menus
o Users interact with the system using a mouse and keyboard
o Easier for beginners to learn and use
Dialogue-based interface
o Users communicate with the system through text or voice
o The system responds with appropriate ac ons or feedback
Gesture-based interface
o
o
Users interact with the system through physical gestures
Requires a camera or sensor to detect movements
dIfferenceS between typeS of InterfaceS
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CLI has a steeper learning curve compared to GUI
GUI is more resource-intensive than CLI
Dialogue-based and gesture-based interfaces enable more natural and intui ve interac on
advantageS & dISadvantageS
Type of Operating
System
Command Line Interface
Advantages
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Faster for experienced users
Consumes fewer system
resources
Disadvantages
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Graphical User Interface
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Dialogue-based &
Gesture-based Interfaces
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User-friendly and easier to
learn
Visually appealing
Be er help facili es
Can exchange data between
different applica ons
Natural and intui ve
interac on
Accessible for users with
disabili es
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Difficult for beginners to
learn
Less visually appealing
Slower for some tasks
compared to CLI
Consumes more system
resources (RAM / HDD)
Slower to run as graphics
have to be loaded
Restric ve as can only use
pre-defined func ons
May require addi onal
hardware
Limited func onality
compared to CLI and GUI
exam tIp
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Make sure you explain your answer in full - GUI requires more power is not enough on
its own and needs expansion
Make sure you know a range of both benefits and drawbacks
analogue & dIgItal data
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Analogue data is continuous and varies smoothly over time
Digital data is discrete and represented in binary form (0s and 1s)
Differences between Analogue & Digital Data
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Analogue data can have any value within a range, while digital data has a limited set of
values
Digital data is less prone to noise and distortion compared to analogue data
Digital data can be easily manipulated, stored, and transmitted by computers
Converting Analogue to Digital Data
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Analogue data must be converted to digital data so it can be processed by a computer
This process is called analogue-to-digital conversion (ADC) and is performed by
an analogue-to-digital converter
Converting Digital to Analogue Data
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Digital data must be converted to analogue data so it can be used to control devices
This process is called digital-to-analogue conversion (DAC) and is performed by
a digital-to-analogue converter
worked example
A greenhouse is used to grow plants and is computer-controlled. Give two reasons why
data from the sensors need to be converted for use by a computer.
[2]
Two of:
So that the data from the sensor can be understood by the computer [1]
The output from a sensor is analogue [1]
The input to the computer is digital [1]