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Year 10 · ICT · Autumn 1 · Computer systems, devices and storage; document production

Hardware, software and user interfaces

TheoryPresent ▶

What this lesson covers

1.1 Hardware and software

Cambridge IGCSE ICT 0417 · Topic 1: Types and components of computer systems · Paper 1

1.3 Operating systems

Cambridge IGCSE ICT 0417 · Topic 1: Types and components of computer systems · Paper 1

You will learn to

  • Explain the difference between hardware and software, and between application and system software.
  • Name the internal components of a computer and say what each one does.
  • Describe command line, graphical, dialogue-based and gesture-based interfaces.
  • Compare a command line interface with a graphical interface, and choose one for a given user.

Success criteria

  • I can label the CPU, RAM, ROM and motherboard on a photo.
  • I can give two examples each of application software and system software.
  • I can do the same task in a CLI and a GUI, and give one advantage of each.
The syllabus points for these sections
  • Name the internal components of a computer and say what each one does.
  • Explain the difference between hardware and software.
  • Tell application software apart from system software, with examples.
  • Explain analogue and digital data and why we convert between them.
  • Say what an operating system does.
  • Describe command line, graphical, dialogue-based and gesture-based interfaces.
  • Give an advantage and a disadvantage of each type of interface.
  • Choose a suitable interface for a given user and situation.

Key words

Say each word, then read what it means. Every one is in the glossary too.

Hardware
The physical parts of a computer system that you can touch.
Software
The programs (sets of instructions) that run on the hardware.
Application software
Software that lets the user do a task, such as a word processor.
System software
Software that runs and maintains the computer, such as the operating system and drivers.
Motherboard
The main circuit board that connects all the components.
CPU
Central processing unit: carries out program instructions.
RAM
Random access memory: volatile memory holding the programs and data in use.
ROM
Read-only memory: non-volatile memory holding the start-up instructions.
Analogue data
Data that changes smoothly and can take any value, like temperature.
Digital data
Data made of separate values, stored in binary.
Operating system
System software that manages the hardware, files and programs, and gives the user an interface.
GUI
Graphical user interface: windows, icons, menus and pointers.
CLI
Command line interface: the user types text commands.

The explanation

Read it here, or open the study page below to go one step at a time with things to try.

1.1 Hardware and software

Hardware and software

Hardware is the physical parts of a computer system. You can touch them: a keyboard, a screen, a chip.

Software is the programs that run on the hardware. A program is a set of instructions.

Neither is useful alone. Hardware with no software does nothing. Software needs hardware to run on.

e.g.Example
A school laptop. Hardware: the screen, keyboard, processor, memory, battery. Software: the operating system, the web browser, the word processor.
?Why?

Exam questions often ask you to sort a list into hardware and software. Ask yourself: can I touch it? If yes, it is hardware.

Internal components

Internal components sit inside the computer case.

The motherboard is the main circuit board. Every other part plugs into it, so they can talk to each other.

The graphics card and sound card are extra boards that handle pictures and sound, so the CPU has less work.

The network interface card (NIC) lets the computer connect to a network.

ComponentWhat it does
Central processing unit (CPU)Carries out (executes) program instructions and does the calculations.
MotherboardMain circuit board. Connects the CPU, memory and all other parts.
RAMHolds the programs and data in use right now. Lost when power is off.
ROMHolds the start-up instructions (the BIOS). Kept when power is off.
Graphics cardProcesses image data and sends it to the monitor.
Sound cardTurns digital sound data into signals for speakers, and microphone signals into digital data.
Network interface card (NIC)Connects the computer to a network. Has a unique MAC address.
!Watch out

Do not say the motherboard "stores" data or "processes" data. It connects parts. Processing is the CPU's job.

Application software and system software

Application software lets the user do a task. Examples: word processor, spreadsheet, web browser, video editor, photo editor, database.

System software runs and looks after the computer itself. It lets application software work. Examples: the operating system, device drivers, utilities such as anti-virus and disk defragmenter, compilers and linkers.

A device driver is a small program that lets the operating system talk to one piece of hardware, such as a printer.

Application softwareSystem software
PurposeDoes a job for the userControls and maintains the computer
Who uses itThe user, directlyMostly the computer; runs in the background
Needed to run the computer?NoYes (at least the operating system)
ExamplesSpreadsheet, browser, graphics editorOperating system, driver, anti-virus, compiler
?Why?

The test is: does it help the user do a task (application), or does it help the computer run (system)?

Analogue and digital data

Analogue data changes smoothly and can take any value. Temperature, sound waves and light levels are analogue.

Digital data is made of separate values, stored as binary (1s and 0s). Computers only understand digital data.

So analogue data from the real world must be converted to digital before a computer can use it. An analogue-to-digital converter (ADC) does this.

To control something in the real world, such as a speaker or a motor, digital data is changed back with a digital-to-analogue converter (DAC).

e.g.Example
A greenhouse temperature sensor sends an analogue signal. ADC changes it to binary, e.g. 22 °C becomes 00010110. The computer compares it with the set value. To play a warning through a speaker, a DAC turns the digital sound back into an analogue signal.
!Watch out

Say "a computer can only process digital data". That phrase is the mark for "why convert".

1.3 Operating systems

What an operating system does

An operating system (OS) is the system software that runs the computer. It is loaded when the computer starts.

It manages memory, files and folders, input and output devices, security (user accounts) and the running of programs.

It also gives the user an interface: the way the user and the computer communicate.

Command line and graphical user interfaces

A command line interface (CLI) is text only. The user types commands, such as `copy report.docx backup`.

A graphical user interface (GUI) uses windows, icons, menus and a pointer (WIMP). Smartphones use a post-WIMP GUI where you tap and swipe instead of using a pointer.

CLIGUI
AdvantageThe user has direct control and can do things the GUI cannot; uses little memory and processing powerEasy to learn, no commands to remember, so good for beginners
DisadvantageMust learn and remember commands; typing errors stop commands workingUses more memory and processing power; some advanced settings are hidden
Typical userNetwork manager, technician, programmerOffice worker, student, home user
!Watch out

Compare both sides; a description alone is not enough. "A GUI is easier to use than a CLI because the user does not need to remember commands."

Dialogue-based and gesture-based interfaces

A dialogue-based interface lets the user talk to the computer. Voice assistants in phones, smart speakers and cars use it. The computer replies with speech.

A gesture-based interface reads body movements, such as a hand wave or a swipe in the air, using a camera or motion sensor. Games consoles and some cars use it.

Dialogue-based (voice)Gesture-based
AdvantageHands-free, so safer when driving; helps people with limited movementNo touching, so more hygienic (e.g. in a hospital); feels natural
DisadvantageBackground noise and accents cause errors; limited set of commandsAccidental movements can trigger commands; user must learn the gestures
Example"Call home" in a carWaving to skip a song on a car screen
e.g.Example
Exam style: "A driver wants to change the radio station. Give one advantage of a dialogue-based interface." Answer: The driver can keep both hands on the wheel, because they speak the command instead of pressing buttons.

Study it

Open the study page and go one step at a time.

ICT topic 1

Types and components of computer systems

Step by step, with exam questions and a quiz.

ICT topic 2

Input and output devices

Step by step, with exam questions and a quiz.

ICT topic 3

Storage devices and media

Step by step, with exam questions and a quiz.

ICT topic 11

File management

Step by step, with exam questions and a quiz.

ICT topic 17

Document production

Step by step, with exam questions and a quiz.

Topic 1 · Year 7

What a computer is

A computer takes information in, follows instructions to change it, and gives a result out. It does all of this with billions of tiny on/off switches.

Topic 8 · Year 8

Inside the computer

The CPU does the work, RAM holds what it's using now, and storage keeps everything long-term. The CPU repeats one loop: fetch, decode, execute.

Check yourself

One question at a time. The reason shows after each answer.

Saved on this device.