New
New
Why do computers use binary?
I can explain why computers use binary to represent all data and instructions.
Lesson 1 of 6
New
New
- Year 10
- AQA
Why do computers use binary?
I can explain why computers use binary to represent all data and instructions.
Lesson details
Key learning points
- Computers use binary to represent all data and instructions.
- Binary is a number system consisting of 1s and 0s.
- Binary can be represented by two-state electrical signals within circuits.
- A transistor that is “on” represents a 1; a transistor that is “off” represents a 0.
Keywords
Data - facts and figures in their raw form
Binary - a number system that uses the digits 0 and 1 to represent data
Instruction - directions on how to carry out a specific task
Transistor - a tiny electronic switch controlled by electricity
Common misconception
Computers use binary for data and instructions but they can use other number systems just as easily.
Computers have to use binary as they are powered by electrical circuits which contain transistors which can be switched on and off using electricity. Using other number systems would require more complex circuitry.
When getting students to think about the number of possible combinations it is useful for them to write out each possible combination in a table. This will also help when they start binary conversions later in the unit.
Teacher tip
Equipment
Licence
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Lesson video
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Prior knowledge starter quiz
6 Questions
Q1.People may write a message for a number of reasons. Which of these is NOT a reason to write a message?
People may write a message for a number of reasons. Which of these is NOT a reason to write a message?
to send information across a long distance
to share knowledge
to tell a lot of people something at the same time
Q2.Written messages can appear in many forms. Put these forms of writing into date order, from oldest to most recent.
Written messages can appear in many forms. Put these forms of writing into date order, from oldest to most recent.
Q3.A computer can store and instructions.
A computer can store and instructions.
Q4.Select all the ways that a light bulb can appear.
Select all the ways that a light bulb can appear.
both on and off at the same time
Q5.What is the next number in this sequence: 1, 2, 4, 8…?
What is the next number in this sequence: 1, 2, 4, 8…?
Q6.What does the word 'binary' mean?
What does the word 'binary' mean?
one
ten
many
Assessment exit quiz
6 Questions
Q1.Match the words to the correct description.
Match the words to the correct description.
Q2.Why do computers use binary?
Why do computers use binary?
Binary allows messages to be encoded so hackers can’t read them.
It is the easiest language to program in.
Computers only deal with numbers.
Q3.What types of data can be represented by binary when stored on a computer?
What types of data can be represented by binary when stored on a computer?
emotion
light
Q4.If 1001 represents on, off, off, on, what does 01 represent?
If 1001 represents on, off, off, on, what does 01 represent?
Q5.Write the binary number that would represent off, on, on, off, off, on, off, on. You don’t need any spaces or punctuation.
Write the binary number that would represent off, on, on, off, off, on, off, on. You don’t need any spaces or punctuation.
Q6.Five binary digits allow 32 combinations, six binary digits allow 64 combinations. How many combinations can we represent with eight binary digits?
Five binary digits allow 32 combinations, six binary digits allow 64 combinations. How many combinations can we represent with eight binary digits?
128
512
1024
