Octal numbers are made up only of the digits \(\{0,1,2,3,4,5,6,7\}\). Each place in an octal number corresponds to a power of \(8\).

Because there are only \(8\) different possible digits in an octal number, we also call them Base \(8\) numbers.

For example, the octal number \(374\) is equal to the decimal number \(3 \times 8^2 + 4 \times 8^1 + 7 \times 8^0 = 3 \times 64 + 4 \times 8 + 7 \times 1 = 231\).

Some other examples of octal numbers are:

• \(77\), which corresponds to the decimal number \(63\).
• \(100\), which corresponds to the decimal number \(64\).
• \(101\), which corresponds to the decimal number \(65\).