base 12 is a positional numeral system with twelve as its base. It uses 12 different digits for representing numbers. The digits for base 12 could be 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, a, and b.
quaternary (base 4)
Quaternary is the base-4 numeral system. It uses the digits 0, 1, 2 and 3 to represent any real number.