What is Hexadecimal?

Hexadecimal is a base-16 number system that uses sixteen symbols: 0–9 and A–F. Because one hex digit maps neatly to four binary bits, it is a compact way to represent binary data — used for memory addresses, color codes (#FF8800), and byte values.

Two hex digits represent one byte (0–255). Hex is often prefixed with 0x in code, e.g. 0x1F equals 31 in decimal.