Good Learning Co.
SavannahYear 8
← Computing
ComputingHow computers represent the world26 min★★ difficulty

Hardware, software and how they communicate

Behind every app is a chain of hardware components passing data to each other, controlled by software instructions.

Part of your national curriculum
  • Data and representation: Understand the hardware and software components that make up computer systems, and how they communicate with one another to process data

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 to process data

Key learning points

  • • Core hardware components
  • • The fetch-decode-execute cycle
  • • Software directs the hardware

This lesson at a glance

  • 26 minutes
  • 14 parts to scroll through
  • 3 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 14 · Discover7%
1

Watch & discover

Part 1 of 14

Watch first

Hardware, software and how they communicate

An English teaching video on this topic from Prototype Education. Watch it, then scroll down for the lesson.

In a nutshell

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

2

Learning cycle

Part 2 of 14

Learning cycle 1 of 2

Part 1 · Core hardware components

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

3

Explore the idea

Part 3 of 14

Learn

Core hardware components

The CPU (processor) carries out instructions, RAM holds data being worked on right now, and secondary storage (SSD/hard drive) keeps files when the power is off. Input devices like keyboards send data in; output devices like screens send results out.

4

Explore the idea

Part 4 of 14

Learn

The fetch-decode-execute cycle

The CPU fetches an instruction from memory, decodes what it means, then executes it — repeating billions of times a second. This simple cycle, running extremely fast, is how software 'runs' on hardware.

5

Quick check

Part 5 of 14

Quick check

Which component temporarily holds data the CPU is currently using?

6

Reset break

Part 6 of 14

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
7

Quick check

Part 7 of 14

Quick check

What are the three stages of the CPU's basic cycle?

8

Learning cycle

Part 8 of 14

Learning cycle 2 of 2

Part 2 · Software directs the hardware

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

9

Explore the idea

Part 9 of 14

Learn

Software directs the hardware

The operating system manages hardware resources and lets application software (like a word processor) request them, for example asking the OS to save a file to storage or send data to the printer via a driver.

10

Quick check

Part 10 of 14

Quick check

What role does an operating system play?

11

Challenge round

Part 11 of 14

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

12

Challenge round

Part 12 of 14

Game · Fill the gaps

Finish the sentences

Choose the word that belongs in each gap.

This simple cycle, running extremely fast, is how software 'runs' on ____.

The operating system manages hardware resources and lets application ____ (like a word processor) request them, for example asking the OS to save a file to storage or send data to the printer via a driver.

13

Mastery quiz

Part 13 of 14

Marked quiz

End of lesson quiz: Hardware, software and how they communicate

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

  1. 1. Which component temporarily holds data the CPU is currently using?

  2. 2. What are the three stages of the CPU's basic cycle?

  3. 3. What role does an operating system play?

14

Lesson round-up

Part 14 of 14

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 3 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 14 · Watch & discover

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

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