What is Hexadecimal?
Hexadecimal is a number system that uses 16 symbols: 0-9 and A-F, where A=10, B=11, C=12, D=13, E=14, F=15. It is widely used in web color codes (#FF0000), memory addresses, MAC addresses, etc. Four binary digits can be simply expressed as one hexadecimal digit, making it very efficient.