# Decimal, Binary, Octal, Hexadecimal Number Systems

**Number System**

A number system of base **r** is a system that uses distinct symbols for **r** digits.

There are four types of number system-

**Decimal number system****Binary number system****Octal number system****Hexadecimal number system**

**Decimal Number System:**

Decimal number system has base 10. This number system contains 10 digits. These are 0,1,2,3,4,5,6,7,8,9. So this number system has base 10.

For e.g. (456)_{10}

**Binary Number System:**

In Binary number system number can be represented using 2 digits

(0 and 1) only .so it has base 2.

For e.g. (101101)_{2}

**Octal Number System**:

In Octal number system number can be represented using 8 digits These are 0,1,2,3,4,5,6,7.so it has base 8 .

For e.g. (3457)_{8}

**Hexadecimal Number System:**

In HexadecimalÂ number system number can be represented using 16 digits These are 0,1,2,3,4,5,6,7,8,9,A,B,C,D,E,F where A=10 B=11,C=12,D=13,E14,F=15

For e.g. (345A)_{ 16}