Hexadecimal

Hexadecimal is widely used by computer system designers and programmers because it can represent every byte (ie eight bits) as two hexadecimal digits instead of eight digits that would be required by binary. Each hexadecimal digit represents four binary digits(bits).
One hexadecimal digit represents a nibble (four bits).
Hexadecimal is a base 16 number system as it consists of 16 characters (numbers and letters) as shown on the table to the bottom left.
In this table on the bottom right of the page there is hex numbers and binary as you can see it consist of 16 hex characters on the right and 16 binary numbers on the left. To work out how to get the hex letters in binary you choose a letter you want to work out I choose A6. You can see that A is the tenth character in hex and 6 is the 6th character in hex. They got the binary for this character by adding up the denary under the 1’s.