February 28, 2025
Octal Number System
Octal notation offers another means of representing numeric values. Unlike decimal, it is based on 8, or radix of 8, rather than 10, i.e. increasing powers of 8. Octal numbers can be represented by using a combination of 0, 1, 2, 3, 4, 5, 6, 7. For example, the decimal number 1209 is represented in the octal 2271
= 2x512 + 2x64 + 7x8 + 1x1
| 83=512 | 82=64 | 81=8 | 80=1 |
| 2 | 2 | 8 | 1 |
2x512=1024 + 2x64=128 + 7x8=56 + 1x1=1
An octal digit (0 to 7) can represent 3 bits (000 to 111). Consequently it
can be regarded as a shorthand version of binary.
Octal notation was widely used to provide a more readable view of binary data.
It has been mostly replaced by hexadecimal notation.
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