KS3 Computing and ICT
Year 8 - DATA REPRESENTATION
Name:
Class:
2
Explain some of the benefits
of using the Binary System for
Computers.
Explain some of the
drawbacks for Computers
using Binary and why
Computers can only work with
two states (on / off).
Explain why humans use
Denary and computers use
Binary.
Be able to convert between
Denary and Binary numbers,
no longer than 4 bits.
Be able to convert between
Denary and Binary numbers,
with up to 1 byte.
Be able to add 2 binary
numbers, no longer than 4
bits.
Be able to add 2 binary
numbers, with up to 1 byte.
Be able to subtract 2 binary
numbers, no longer than 4
bits.
Be able to subtract 2 binary
numbers, with up to 1 byte.
Including, numbers which
involve a carry.
Be able to explain what
Hexadecimal is.
Describe why humans use
Hexadecimal.
Explain some of the benefits
of using the Hexadecimal
system for Humans.
Convert between 8 bit binary
numbers and Hexadecimal.
Be able to explain what Binary Describe why Computers use
is.
Binary.
Be able to explain what
Denary is.
3
Learning Aim: Explain what are binary numbers
✖
✖
✖
Be able to explain what Binary is.
✖
Explain some of the drawbacks for Computers using Binary
and why Computers can only work with two states (on / off).
Describe why Computers use Binary.
Explain some of the benefits of using the Binary System for
Computers.
4
What do I know about binary?
What do I Know
What am I Wondering?
This should be a question!
What have I Learnt?
5
What is binary?
✖
Binary is a base 2 number system
✖
Has only 2 values: 0 and 1
✖
Computer can only understand binary so we have to
convert the data from base 10 (decimal or normal
numbers) into binary which can be understood by the
computer
6
Activity 1 – Research binary. Create a poster which answers the
following:
explain what binary numbers are
✖ Describe why computers use binary – use
images to help you
✖ Explain some of the advantages of the
binary system
✖ Explain some of the disadvantages of the
binary system
7
Self/ Peer assessment - Activity 1 – Research about binary






Create a poster which explains how computers use binary.
My poster describes why computers use binary
My poster explains some of the advantages of the binary system
My poster explains some of the disadvantages of the binary system
I have used colours, text and images to design my poster
I have the date and title
What went well:
Even better if:
8
My poster version 1
9
My poster version 2 – after feedback and improvements
10
BITS and BYTES
✖ a "bit" is atomic: the smallest unit of
storage
✖ A bit stores just a 0 or 1
✖ Group 8 bits together to make 1 byte
11
•1 bit - 2 patterns
•2 bits - 4
•3 bits - 8
•4 bits - 16
•5 bits - 32
•6 bits - 64
•7 bits - 128
•8 bits - 256 - one byte
Bits and Bytes
✖
✖
✖
✖
1 byte is group of 8 bits
8 bits can make 256 different patterns
How to use the 256 patterns?
How to store a number in a byte?
2^8
2^7
2^6
2^5
2^4
2^3
2^2
2^1
2^0
8 bits
7 bits
6 bits
5 bits
4 bits
3 bits
2 bits
1 bit
0 bits
256(
1
byte)
128
64
32
16
8
4
2
0
12
13
Remember to use
BIDMAS
Activity 1 – work out the following binary math problems
Bits
What numbers do I need to
multiply?
Total number of bytes
2x2x2
8 bytes
0
1
2
3
4
5
6
7
8
14
Converting from binary to denary (decimal numbers)
16
0
8
1
4
1
0 + 8 + 4 + 0 + 1
= 13
2
0
1
1
Add up the numbers with a
1 in the column. This will
give you the number in
decimal.
01101 = 13 in decimal.
15
Activity 2 – convert the following binary numbers. Remember to
show your working out and use the table
1010
1110
0011 1111
1010 1010
1110 0011
1111 1111
11
010
1100
128
64
32
16
8
4
2
1
16
Self/peer assessment
Binary
Decimal/ Denary
1010
10
1110
14
0011 1111
63
1010 1010
170
1111 1111
255
11
3
010
2
1100
12