Numerical digit

In mathematics and computer science, a numerical digit is a symbol (a number symbol, e.g. "3" or "7") used in numerals (combinations of symbols, e.g. "37"), to represent numbers, (integers or real numbers) in positional numeral systems. The name "digit" comes from the fact that the 10 digits of the hands (the fingers and thumbs) correspond to the 10 symbols of the common base 10 number system, i.e. the decimal digits.

Examples:
* the characters "0" through "9" in the decimal system
* the characters "0" and "1" in the binary system
* the characters "0"..."9", "A",...,"F" in the hexadecimal system

In a given number system, if the base is an integer, the number of needed digits, including zero, is always equal to the absolute value of the base.

Digits "place"

In the decimal system, digits in a number are given names based on their multiplier. For example, in the number 123.45::the "1" is in the 100s place and so is the 100s digit,:the "2" is in the 10s place and so is the 10s digit,:the "3" is in the 1s place (sometimes called units place), and so is the 1s digit or units digit,:the "4" is in the 10^ths place and so is the 10^ths digit, and:the "5" is in the 100^ths place and so is the 100^ths digit.

References

* Federal Standard 1037C