Arithmetic or
arithmetics (from the
Greek arithmos, "
number") is the oldest and most elementary branch of
mathematics. It consists of the study of
numbers, especially the properties of the traditional
operations between them—
addition,
subtraction,
multiplication and
division. Arithmetic is an elementary part of
number theory, and number theory is considered to be one of the top-level divisions of modern mathematics, along with
algebra,
geometry, and
analysis. The terms
arithmetic and
higher arithmetic were used until the beginning of the 20th century as synonyms for
number theory and are sometimes still used to refer to a wider part of number theory.
