denary

Denary, in English usage, refers to the decimal or base-10 numeral system. It uses ten distinct digits, 0 through 9, and place-value notation, so a number’s value depends on the position of each digit and the corresponding power of ten. Fractions are written using a decimal point, enabling termination or recurring decimal representations. In English, denary is sometimes used interchangeably with decimal, though decimal is more common in modern technical language.

The denary system is the most widely used numeral system in everyday life, science, commerce, and education. Its popularity is linked to historical counting practices and the common use of ten fingers. In mathematics and pedagogy, denary arithmetic encompasses addition, subtraction, multiplication, and division in base-10, as well as decimal fractions and percentages.

In computing, numbers are typically stored and processed in binary, but decimal representations remain essential for user interfaces, input/output, and financial calculations. Specialized formats such as decimal floating point or binary-coded decimal support exact decimal arithmetic when required, balancing human readability with machine processing.

See also: decimal system, base-10, place-value notation.