Numeral

Numeral is a symbol or combination of symbols used to express a number in a given numeral system. It is distinct from the number itself, which is the abstract concept of quantity.

Most commonly, numerals are used within a decimal system that employs ten digits (0–9) and place-value notation. The symbol "123" is a decimal numeral for the number one hundred twenty-three. Other numeral systems include Roman numerals (I, II, III, IV, V, etc.), Devanagari digits (०–९), and Chinese numerals. The term numeral can refer to the written symbol itself or to the set of symbols used in a script.

Digits are the basic symbols used in a particular system; numerals may be multi-digit and may involve combining digits with place-value rules. In non-positional systems like Roman numerals, the same symbol can have different values depending on context.

Historically, numerals developed from tally marks and other counting devices. The concept of zero and place value was developed in India, transmitted westward through Arabic scholars to medieval Europe, enabling the modern decimal numeral system.

In computing, numeral bases extend beyond decimal, such as binary (base-2), octal (base-8), and hexadecimal (base-16). In these bases, numerals use limited digit sets (e.g., 0–1 in binary; 0–9 and A–F in hexadecimal). The term numeral thus encompasses both the symbols used to write numbers and the systems that organize those symbols.