Octal uses 8 digits (0-7) and is primarily used in some traditional computer systems and Unix file permissions.

• Uses digits 0-7
• Widely used in early computer systems
• Each octal digit represents 3 binary bits
• Often uses '0' prefix, such as '0o755'

Binary is the most basic representation of data in computing, using only 0s and 1s.

• Each bit can only be 0 or 1
• Forms the foundation of all digital systems
• Usually grouped in 8-bit bytes
• Can be represented with a prefix like '0b101010'