base 14 is a positional numeral system with fourteen as its base. It uses 14 different digits for representing numbers. The digits for base 14 could be 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, a, b, c, and d.

base 18 is a positional numeral system with eighteen as its base. It uses 18 different digits for representing numbers. The digits for base 18 could be 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, a, b, c, d, e, f, g, and h.