The binary numeral system, is the **base-2** number system, and uses the digits 0 and 1.

Because of its importance in digital technology, it is next to the decimal system, the most
important number system

The octal numeral system, is the **base-8** number system, and uses the digits 0 to 7.

The system is used in computer engineering. Each octal number can be represented by three bits.

The decimal numeral system, is the **base-10** number system, and uses the digits 0 to 9.

The probable starting point of the decimal counting are the ten fingers on two hands.
The system is next to the binary system the most important number system.

The hexadecimal numeral system, is the **base-16** number system, and uses the digits 0 to 9 and A
to F.

Hexadecimal numerals are widely used by programmers, as they provide a human-friendly representation
of binary values.