← ACARA Digital Technologies Years 7–8

Explaining why digital technology uses binary

A clear explanation says digital hardware has two states (on and off), so it stores numbers as 0s and 1s, and it gives the reason using the word because.

Part of: ACARA Digital Technologies Years 7–8 — Binary Number Representation — Module 30

Understanding Explaining why digital technology uses binary in ACARA Digital Technologies Years 7–8

What it does: The starter ends in because, so the student must finish it with the reason: the hardware has two states. It uses an everyday switch, simple words and because to explain why computers use two digits. 'Because' links the fact to its reason. 'And' only adds more facts without explaining anything. A switch has two states, on and off. Binary matches this by using only two digits, 0 and 1. The second sentence only says what computers use. The first one explains why, using because. A good explainer script states the question, then answers it by linking the hardware's two states to the use of 0 and 1.

Common mistakes: Digital hardware has two states, not ten. The line should say 'hardware has two states,' so the 0s and 1s make sense. Two states can only be stored as the two digits 0 and 1, not 0 to 9. It should say 'so it stores data as 0s, 1s.'.

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This module's key terms are also in a printable crossword (Modules 204–236) and word search (Modules 189–236).

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Learning

Duo

Which sentence gives a clear reason why computers use binary?

Computers use binary because their hardware has two states, on and off.Computers use binary. It is how they work.

Matches

Computers use binary.

↓

It states a fact but gives no reason. There is no because and no mention of the two states (on and off) in the hardware.

Applying

Meanings

Term

Computers use binary because their hardware has two states

Meaning

A clear explanation says digital hardware has two states (on and off), so it stores numbers as 0s and 1s, and it gives the reason using the word because.

Practice

Computers use binary because their hardware has two states.

Testing

Gaps

Computers use binary hardware has

Check Answer

Spots

1Computers use binary because

2hardware has ten states,

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Quick Questions

1. Which sentence gives a clear reason why computers use binary?

A. Computers use binary. It is how they work.

B. Computers use binary because their hardware has two states, on and off. ✓

A clear explanation uses the word because to give a reason: the hardware has two states, so 0 and 1 can represent them.

2. Which sentence starter helps you explain WHY computers use 0s and 1s?

A. Digital hardware stores numbers as 0s and 1s because... ✓

B. Digital hardware stores numbers as 0s and 1s and...

'Because' links the fact to its reason. 'And' only adds more facts without explaining anything.

3. Which explanation refers to switches and hardware correctly?

A. A switch has ten settings, so it can store the digits 0 to 9.

B. A switch is either on or off, so it can store a 0 or a 1. ✓

A switch has two states, on and off. Binary matches this by using only two digits, 0 and 1.

4. You are explaining binary to a younger student. Which is the better explanation?

A. It's like a light switch. It can only be on (1) or off (0), so computers use just those two digits. ✓

B. Binary is a base-2 positional numeral system used for encoding data in digital logic circuits.

A simple comparison with something familiar, like a light switch, makes the reason easy for a younger student to understand.

5. Which statement is a reason, not just a fact?

A. Computers use binary because electronic circuits have two states. ✓

B. Computers use binary numbers made of 0s and 1s.

The second sentence only says what computers use. The first one explains why, using because.

Match the Pairs

Computers use binary because their hardware has two states. → A clear one-sentence explanation: it gives the reason (two states) and uses the word because.

A switch is on (1) or off (0), so it can store one bit. → Refers to switches to show how two hardware states match the two binary digits 0 and 1.

A sentence starter that gives a reason using because → Digital technology uses 0s and 1s because ...

Explaining binary to a younger student using a simple switch idea → Think of a light switch: it is only ever on or off, so computers use 0 and 1 because that is all their parts can do.

Computers use binary. → It states a fact but gives no reason. There is no because and no mention of the two states (on and off) in the hardware.

Computers use binary because they use ten states, 0 to 9. → The reason is wrong. Digital hardware has two states, not ten, so it uses only the digits 0 and 1.

Key Term

Computers use binary because their hardware has two states

A clear explanation says digital hardware has two states (on and off), so it stores numbers as 0s and 1s, and it gives the reason using the word because.

Fill in the Blanks

1. Computers use binary because hardware has two states.

Hint: Type the word that introduces the reason in an explanation.

2. Digital hardware has two states, on and off.

Hint: Type the number of states digital hardware has, written as a word.

3. A switch is on or off, so it stores 1 for on and 0 for off.

Hint: Type the binary digit that stands for the off state.

4. Think of a light switch: on is 1, off is 0, so computers count in binary.

Hint: Type the word for the switch state that matches the digit 0.

5. Hardware has two states, so it stores numbers as 0s and 1s, called binary.

Hint: Type the name of the number system that uses only 0s and 1s.

Spot the Error

Question 1

A Computers use binary because

B hardware has ten states,

C on/off, so it stores 0s, 1s.

Line B — Digital hardware has two states, not ten. The line should say 'hardware has two states,' so the 0s and 1s make sense.

Question 2

A A switch is either on or off.

B Hardware has these two states

C so it stores data as 0s to 9s

Line C — Two states can only be stored as the two digits 0 and 1, not 0 to 9. It should say 'so it stores data as 0s, 1s.'

Question 3

A Imagine a light switch, Sam.

B It is on (1) or off (2).

C Computers use switches too,

D so they use 0s and 1s.

Line B — Binary only has the digits 0 and 1. Off is written as 0, so the line should be 'It is on (1) or off (0).'

Question 4

A Binary has ten digits because

B hardware has two states, on

C and off. One digit matches

D each state.

Line A — Binary has two digits (0 and 1), not ten. The line should be 'Binary has two digits because' to match the two hardware states.

Question 5

A Podcast script: Why binary?

B Host: Computers use binary

C because chips are made of

D tiny dials with ten states

E So data becomes 0s and 1s.

Line D — Chips are made of tiny switches that are on or off. Dials with ten states would not give a reason for binary. It should be 'tiny switches, on or off.'

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