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The hexidecimal number system

What is ​hexadecimal?
Hexadecimal is a number another number system. You can probably count from zero to one hundred in the number system that we are all taught as children. That number system is called denary. Guess what, it is NOT the only number system that exists, there are loads. You are being introduced to "binary" and "hexadecimal" Which means you will be able to understand 3 number systems, denary, binary and hexadecimal.

What is hexadecimal used for?
1. Hexadecimal is a quick way of writing binary numbers and binary is the number system used by all computers
2. Hexadecimal is also used as a quick way to represent colours. 
3. Hexadecimal is used to express Media Access Control (MAC) addresses. If you decide to prank call the police from a mobile phone, they will trace you instantly because your mobile phone has a unique MAC address.
4. Locations in RAM or Disk drives are expressed in Hexadecimal. (If you saved a mp3 music file to your computers hard disk, it would be a bit annoying if your computer forgot where you saved it. )

How does Hexadecimal work?
The hexadecimal number system is really easy to learn especially if:
  • You know how to count to 15 in "denary". (Denary is normal counting that we are taught as children, sometimes its called "decimal" or "base 10")​. Here is how to count to fifteen: 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15. Got it?
If you know how to count from 0 to 15, then it should be easy for you to learn ​hexadecimal. Ready? here we go! In one sentence, when counting up from zero to fifteen in hexadecimal, it is exactly the same as in denary, however when you get up to 10, in hexadecimal there is no 10, instead it is "A", then "B" (which is 11), then C, D, E and F (which is 15). Thats it! (see the table below for help)

So to count to 15 in hexadecimal it goes like this:
​0, 1, 2, 3, 4, 5, 6, 7, 8, 9, A, B, C, D, E, F

This table converts a denary number to the hexadecimal ​ value 

Denary/decimal/base 10
Hexadecimal 
zero
zero
1
1
2
2
3
3
4
4
5
5
6
6
7
7
8
8
9
9
10
A
11
B
12
C
13
D
14
E
15
F

Loading KS3 Hexadecimal
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