Digit

by Hla Min

Updated : Oct 2025

Term

• A digit may stand for a finger.
  The use of ten fingers for counting may have given rise to the Decimal Number System.
• A digit may stand for a symbol of a Number System.

Base

• A Number System has a Base (or Radix). The Base specifies the number of digits used in the system.
• Decimal Number System (Base 10) uses ten digits : 0, 1, 2, 3, 4, 5, 6, 7, 8, 9.
• Binary Number System (Base 2) uses two digits : 0 and 1.
• Octal Number System (Base 8) uses eight digits : 0, 1, 2, 3, 4, 5, 6, 7.
• Hexadecimal Number System (Base 16) uses sixteen digits :
  0, 1, 2, 3, 4, 5, 6, 7, 8, 9, A, B, C, D, E, F.

Computing

• Some early computers and calculators use Base 10.
• Most computers use Base 2 internally. Since binary numbers are long, they are expressed externally using Octal and Hexadecimal.
• Computers and programs support easy Conversion between the Number Systems.

Digital

• Digital displays (read outs) are common.
• There are converters from digital to analog (and vice versa).
• Digital displays (read outs) are common.