CPUs are made up of billions of tiny switches. These switches can either be on or off and cannot work with the numbers we use (denary, 0-9) or our languages. Everything on a computer must be broken down to binary (0s and 1s). 0 = Off 1 = On Humans use denary numbers and It’s difficult for humans to understand binary numbers. We can convert between binary and denary numbers.
At GCSE, you will only ever work with 8 bit numbers - binary numbers which contain 8 ones or zeros. For example:
0110 1110
What happens if you need to display a large binary number such as:
1111 1011 1111 1010 0011
Larger binary numbers are hard to remember and hard to write out without making a mistake. Hexadecimal is a number system (base-16) and makes use of 0-9 and A-F. It allows us to work with binary numbers in a more manageable way. Each 4 bits of a binary number can be represented with 1 hexadecimal digit. For example:
1011 = B
Hexadecimal numbers are used commonly when representing colours on web pages.