Byte

A byte is a group of 8 bits; it has a value ranging from 0 to 255. That is because there are 256 different combinations of binary digits (1s and 0s) when 8 bits exist. The smallest value is 0, so 256 does not exist.

The value can also be obtained by the following calculation which shows the greatest number that could be obtained from the combination of bits which is 11111111.

20 + 21 + 22 + 23 + 24 + 25 + 26 + 27 = 255

1 + 2 + 4 + 8 + 16 + 32 + 64 + 128 = 255