Good Learning Co.
SavannahYear 8
← Computing
ComputingHow computers work20 min★★ difficulty

Inside a computer: hardware and software

Every computer, from a laptop to a games console, has the same main parts working together.

Part of your national curriculum
  • Data and representation: Understand how instructions are stored and executed within a computer system, and how data of various types can be represented and manipulated digitally
  • Computer systems and networks: Understand the hardware and software components that make up computer systems, and how they communicate with one another and with other systems

Lesson overview

What you'll learn in this lesson

Understand the hardware and software components that make up computer systems, and how they communicate with one another and with other systems

Key learning points

  • • Input, process, output
  • • Memory and storage
  • • Fetch, decode, execute
  • • Software layers

This lesson at a glance

  • 20 minutes
  • 19 parts to scroll through
  • 4 quick checks
  • Marked quiz at the end
  • Gentle pace: short sittings with pauses

Words to know

hardwaresoftwarecomponentscomputersystems

Scroll down — the lesson carries on below

Part 1 of 19 · Intro5%
1

Introduction

Part 1 of 19

Inside a computer: hardware and software illustrationVisual introduction

Picture this

Inside a computer: hardware and software

Every computer, from a laptop to a games console, has the same main parts working together.

In a nutshell

Understand the hardware and software components that make up computer systems, and how they communicate with one another and with other systems

2

What you already know

Part 2 of 19

Before we start

What you already know

You've used a computer, phone or tablet.

3

Key words

Part 3 of 19

Key words

Words you'll need today

hardware
The physical parts you could touch.
software
The programs and apps that tell hardware what to do.
CPU
The processor: the 'brain' that carries out instructions billions of times a second.
RAM and storage
RAM holds what's in use right now and empties when switched off. Storage (SSD) keeps files long-term.
4

Learning cycle

Part 4 of 19

Learning cycle 1 of 2

Part 1: The main parts

A short piece of teaching, then a check to make sure it has landed.

5

Explore the idea

Part 5 of 19

Learn

Input, process, output

Input devices send data in (keyboard, mouse, microphone, touchscreen). The CPU processes it. Output devices show the result (screen, speakers, printer).

6

Explore the idea

Part 6 of 19

Learn

Memory and storage

RAM is like your desk: fast, holds what you're working on, cleared at the end of the day. Storage is like a filing cabinet: slower, but keeps everything when the power's off.

7

Quick check

Part 7 of 19

Quick check

Which is hardware?

8

Quick check

Part 8 of 19

Quick check

What does the CPU do?

9

Reset break

Part 9 of 19

Pause

That's sitting 1 of 2 done

Stretch, get a drink, look out of the window. There is no timer and nothing is counting down — your place is saved, so you can come back in five minutes or tomorrow.

Stop here for now
10

Learning cycle

Part 10 of 19

Learning cycle 2 of 2

Part 2: How they work together

A short piece of teaching, then a check to make sure it has landed.

11

Explore the idea

Part 11 of 19

Learn

Fetch, decode, execute

The CPU repeats three steps: fetch an instruction from memory, decode what it means, then execute it. A modern CPU does this billions of times a second.

12

Explore the idea

Part 12 of 19

Learn

Software layers

The operating system (Windows, macOS, Android, iOS) manages the hardware. Applications, like a browser or game, run on top of it.

13

Quick check

Part 13 of 19

Quick check

What happens to RAM when the power goes off?

14

Quick check

Part 14 of 19

Quick check

The CPU's repeated cycle is:

15

Common mix-ups

Part 15 of 19

Common mix-ups

Things people often get wrong

  • More storage doesn't make a computer faster. RAM and the CPU matter more for speed.
  • An app is software. The screen it appears on is hardware.
16

Challenge round

Part 16 of 19

Game · Sort it

Which of these are true?

Drag each card into the right column. Tap a card first if dragging is fiddly.

True

Not true

17

Challenge round

Part 17 of 19

Game · Fill the gaps

Finish the sentences

Choose the word that belongs in each gap.

The operating system (Windows, macOS, Android, iOS) manages the ____.

18

Mastery quiz

Part 18 of 19

Marked quiz

End of lesson quiz: Inside a computer: hardware and software

3 questions, marked with the reasoning shown. No timer.

  1. 1. A microphone is an:

  2. 2. Windows and Android are:

  3. 3. Saved files are kept on:

19

Lesson round-up

Part 19 of 19

Lesson round-up

Ready when you are

Quiz score

Not sat

Games

Not played

Points this lesson

0

Best run

0 in a row

Luna: 0 out of 4 on the practice checks. Only if you feel up to it — one more?

Ask Luna

Do the work

Your written work for this lesson

This is the part you'd do in your book at school. Pick the pieces below, write here or on paper, and photograph anything you draw or work out.

Article

How a supermarket checkout knows the price

When a barcode is scanned, the checkout does not store the price itself. It sends the barcode number to a database and reads back a record: product name, price, whether it needs an age check. The record is the single place the price lives, so changing one row changes every till in the shop at once.

Problems come from bad data, not bad scanners. If two products share a barcode, or a price update reaches the shop overnight but the till holds an old copy in its cache, customers are charged the wrong amount. Shops check this with test transactions: scan a known item, expect a known price, record what actually happened.

Good systems also log every scan. If a customer complains, the log shows exactly which record was used and when.

Written for Good Learning Co.

Reading questions

  1. Write in your own words what the checkout sends and what it receives back.
  2. Explain one way bad data could cause a wrong price, and how logging helps find it.
  3. Design a test table with four tests for a new checkout, with expected and actual results.

  • Reading and notes

    Reading

    Read the lesson text again and note the key terms and how each one is used, in your own words — as you would for revision.

    Half a page of notes

  • Extended writing

    Writing

    Explain a real system that uses this idea — how it works, where it can go wrong, and how you would make it safer or better.

    250–350 words

  • Algorithm on paper

    Diagram

    Write your steps out as pseudocode or a flowchart before you type anything, then photograph it.

    1 flowchart or 10 lines

  • Code write-up

    Writing

    Copy your code in, then explain underneath what each part does and what you had to fix.

    Code + 5 sentences

  • Test table

    Working out

    Make a test table: what you tried, what you expected, what actually happened.

    4–6 tests

Saved as you type.

Part 1 of 19 · Introduction

How this is going

  • Not looked at yet

    Understand how instructions are stored and executed within a computer system, and how data of various types can be represented and manipulated digitally

  • Not looked at yet

    Understand the hardware and software components that make up computer systems, and how they communicate with one another and with other systems

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