Octal
The octal numeral system, or oct for short, is the base-8 number system, and uses the digits 0 to 7. Numerals can be made from binary numerals by grouping consecutive digits into groups of three (starting from the right). For example, the binary representation for decimal 74 is 1001010, which groups into 001 001 010 — so the octal representation is 112 . 112 in octal is equal to 74 in decimal and 4A in hexadecimal .
Octal is sometimes used in computing instead of hexadecimal.