Hexadecimal and Binary – GCSE Computer Science Edexcel Revision

Understanding Hexadecimal and Binary

Hexadecimal is a base-16 number system. It’s made up of 16 symbols: the numbers 0-9 and the letters A-F.
The letter A represents the decimal number 10, B represents 11, and so on, up until F which represents 15.
The use of hexadecimal significantly reduces the length of binary numbers, making them easier to read and understand.
In computing, hexadecimal often represents binary numbers, as each hexadecimal digit can represent four binary digits or bits.
This four-bit group is also known as a nibble, and two nibbles make a byte.

To convert binary to hexadecimal, you group the binary number into nibbles from the right and then convert each nibble separately into its hexadecimal equivalent.
For example, the binary number 10110011 can be split into the nibbles 1011 and 0011. These in turn are equivalent to the hexadecimal digits B and 3 respectively. So 10110011 in binary is B3 in hexadecimal.

To convert hexadecimal to binary, you convert each hexadecimal digit into its four-bit binary equivalent.
For example, the hexadecimal number A9 is made up of the digits A and 9. A is 1010 in binary and 9 is 1001 in binary. So A9 in hexadecimal is 10101001 in binary.

Hexadecimal is extensively used in programming and computing because it is concise and easier to read than binary, particularly when dealing with large numbers or colour codes.
It also provides an easily readable and writable representation of binary data, while still maintaining a strong correlation to the binary structure, thereby enabling easier debugging and examination of system-level data.