The decimal numeral system (also called base-ten positional numeral system, and occasionally called denary) is the standard system for denoting integer and non-integer numbers. It has ten as its base.
base 4
base 4 is a positional numeral system with four as its base. It uses 4 different digits for representing numbers. The digits for base 4 could be 0, 1, 2, and 3.