The word "Arithmetic" is from Greek "arithmos", meaning "number". Arithmetic is the most basic form of mathematics. It concerns counting and working with numbers and fractions based on the four operations: addition, subtraction, multiplication and division although the more advanced operations, such as manipulations of percentages, square root, exponentiation and logarithmic functions, are also a part of this subject. Arithmetic is performed according to an order of operations. Historically, the researchers have found that the initial significance of arithmetic had been realized during the third century B.C.

The term "arithmetic" is also used to refer to elementary number theory; it’s in this context that one runs across the fundamental theorem of arithmetic and arithmetical functions.

Arithmetic is used by almost everyone, for tasks ranging from simple day–to–day counting to advanced science and business calculations.