base 10 is a positional numeral system with ten as its base. It uses 10 different digits for representing numbers. The digits for base 10 could be 0, 1, 2, 3, 4, 5, 6, 7, 8, and 9.

base 13 is a positional numeral system with thirteen as its base. It uses 13 different digits for representing numbers. The digits for base 13 could be 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, a, b, and c.