KS3 · Computer Science

Hardware and software

Pick up a USB stick with a game saved on it. You're holding hardware — but are you holding the game? Working out why not is the whole trick.

Computing · Hardware or software?

Physical part, or set of instructions?

Pick an item, then choose where it belongs. Commit first — the reason appears after you place it.

Still to sort

Hardware (0)

The physical parts of a computer system — you can see and touch them.

Where the line is: Could you pick it up, even if you'd need a screwdriver to get at it? Then it's hardware.

Software (0)

Programs: sets of instructions that tell the hardware what to do.

Where the line is: Software is always stored on hardware, but being stored on something doesn't make it that thing.

10 of 10 still to sort.

Finished? Look back at the USB flash drive and the game saved on it. Why did they end up in different columns?

Computing · Inside or plugged in?

Where does each part of the hardware fit?

Picture a desktop computer with a separate keyboard, mouse, monitor and printer. Tick every box that's true for each part, then check your grid.

CPU (processor)
Main memory
Built-in storage drive
Keyboard
Mouse
Monitor
Printer

Two kinds of software

System softwarevsApplication software

All software is instructions. The split is about the job: looking after the computer, or doing a task for you?

Focus

Its job

System software

Runs and manages the computer itself

Application software

Lets you carry out a task: writing a document, editing an image, browsing the web, playing a game

The insight

The quickest test for any program: is it looking after the computer, or doing something for you?

The big one

System software

The operating system: it manages the hardware (processor, memory and storage), manages files, runs your applications and gives you the user interface you click and tap on

Application software

Whichever app you open for the job in hand — a web browser to visit a website, a word processor to write an essay

Looking after the computer

System software

Utility software: anti-malware, backup tools and file organisers help keep the computer healthy and your files safe

Application software

Not its job: a game or a photo editor won't check for malware or back up your files

Examples

System software

Operating system, anti-malware, backup tool, file organiser

Application software

Word processor, photo editor, web browser, game

Predict, then check

Commit to an answer before you reveal it.

A computer has every piece of hardware it needs — CPU, main memory, storage, keyboard, monitor — but no software at all. Not even an operating system. You press the power button. What can it do?

Computer Science · Structure

How the parts talk to each other

Tap any part to see what travels along its connections. Arrows show which way data can go.

This computer systemnetwork

Tap any part of the diagram to see what it does.

WHAT YOU'VE LEARNED

A quick recap of today's lesson.

The parts you can touch, the instructions you can't — and why a computer is useless without both.

What you need to know

  • Hardware is the physical parts of a computer system: you can see and touch them.
  • Software is programs — sets of instructions that tell the hardware what to do. It has no physical form of its own, although it's always stored on hardware.
  • Internal components (the CPU, main memory and storage) are inside the computer; input devices put data in and output devices give results out.
  • System software runs and manages the computer: the operating system is the main one, and utility software helps look after it. Application software lets you do tasks.
  • Hardware and software need each other, and the hardware is connected so data and instructions can pass between the parts — and to other computers over a network.

The big picture

Every computer system is built from two kinds of thing. Hardware is the physical parts you can see and touch; software is the programs — sets of instructions — that tell the hardware what to do. Some hardware sits inside the computer (CPU, main memory, storage), while input and output devices connect to it from outside. Software is grouped into system software, which runs and looks after the computer (the operating system and utilities), and application software, which does tasks for you. Neither half is any use without the other, and the parts are connected so data can pass between them and on to other computers.

Key points

1Physical part or set of instructions? That one question decides hardware or software.
2Stored on hardware isn't the same as being hardware: the USB stick is hardware, the game on it is software.
3The operating system manages the hardware and files, runs applications and provides the user interface.
4Anti-malware, backup and file-organising tools are utility software — a kind of system software.
5No software, no useful computer; no hardware, nowhere for software to be stored or run.

Worked example

Problem

Your friend says: "The camera app on my phone is hardware, because it's on my phone." Is your friend right? Sort out the phone and the app, and explain.

⚠ Watch out

Deciding by location instead of by what something is. Main memory is inside the computer and it's still hardware; a program downloaded onto a laptop is still software. Where a thing is kept never changes which kind it is.

🧠

Memory hook

If you could drop it on your foot, it's hardware. If you could only copy it, it's software.

✓

Check yourself

Cover the page. Is a webcam hardware or software? A spreadsheet program? Say why for each, then say whether the spreadsheet program is system or application software.

Flashcards

(13)
What is hardware?
The physical parts of a computer system that you can see and touch — for example the CPU, memory, storage, and input and output devices.
What is software?
Programs: sets of instructions that tell the hardware what to do. Software has no physical form of its own.
A game is saved on a USB stick. Which is hardware and which is software?
The stick is hardware; the game is software. The game is stored on the stick, but it isn't the stick.
Why can't hardware do anything useful on its own?
It has no instructions. Hardware only does what software tells it to do.
Why does software need hardware?
Software has to be stored on hardware and run on hardware.
What are internal components? Name three.
Hardware inside the computer: the CPU, main memory and storage.
What does an input device do? Give two examples.
It puts data into the computer — for example a keyboard or a mouse.
What does an output device do? Give two examples.
It gives results out from the computer — for example a monitor, speakers or a printer.
What is system software?
Software that runs and manages the computer itself, such as the operating system and utility software.
What is application software?
Software that lets you carry out a task, such as writing documents, editing images, browsing the web or playing games.
What four jobs does the operating system do?
It manages the hardware (processor, memory, storage), manages files, runs application software and provides the user interface.
What is utility software? Give an example.
System software that helps look after the computer — for example anti-malware software, or a tool that backs up or organises files.
How do the parts of a computer communicate?
They're connected so data and instructions can pass between them, and a computer can exchange data with other computers over a network.

Tap any card to flip it, or use Study as deck to go through them one at a time. In the full lesson these run as a spaced-repetition deck — you rate each card Hard, Good or Easy and the tricky ones keep coming back until they stick.

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