base 7 is a positional numeral system with seven as its base. It uses 7 different digits for representing numbers. The digits for base 7 could be 0, 1, 2, 3, 4, 5, and 6.

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.