# place-value system

A place-value system is a number system in which the value
of a number symbol depends not only on the symbol itself but also on the
position it occurs. The **sexagesimal system** of the Babylonians, with base 60, our own **decimal system**, with base 10, and the binary system (base 2), used in computers, are examples. Each place-value system has a positive integral base and as many different number-symbols as this base allows.

A sexagesimal system must thus have 60 number-symbols; the decimal system uses the symbols 0, 1, 2, 3, 4, 5, 6, 7, 8, and 9; a binary system can use the symbols 0 and 1.