As binary numbers get longer and longer, a new base had to be introduced: hexadecimal numbering.
The hexadecimal number system counts using base 16, so after the first 10 digits come the first six letters: 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, A, B, C, D, E, F.
| Decimal | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 |
| Hexadecimal | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | A | B | C | D | E | F |
| Binary | 0000 | 0001 | 0010 | 0011 | 0100 | 0101 | 0110 | 0111 | 1000 | 1001 | 1010 | 1011 | 1100 | 1101 | 1110 | 1111 |
The number 27 (in base 10) is, in base 16: 1*161 + 11*160 = 1*161 + B*160
that is, 1B in base 16.
The number FB3 (in base 16) is, in base 10: F*162 + B*161 + 3*160 = 3840 + 176 + 3 = 4019
A byte is converted into hexadecimal by splitting it into two groups of 4 bits each, each of which corresponds to a hexadecimal digit.
| 2 | A | D | 5 |
| 0010 | 1010 | 1101 | 0101 |
