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