Meaning eight in Greek (Okta), octal is shorthand for human readability of six-bit binary characters, which were the common memory and storage configurations in earlier computers. Today, the eight-bit byte is the common structure.
In octal, three bits are converted into a single octal digit. Decimal numbers zero to seven are the same as octal numbers because three bits hold eight values. The following example shows octal and hexadecimal notation, which are both shorthand for human readability. See
byte and
hex.
6-Bit 8-Bit
Binary Octal Binary Hexadecimal
000 000 00 0000 0000 00
000 001 01 0000 0001 01
000 010 02 0000 0010 02
000 011 03 0000 0011 03
000 100 04 0000 0100 04
000 101 05 0000 0101 05
000 110 06 0000 0110 06
000 111 07 0000 0111 07
0000 1000 08
0000 1001 09