Arithmetic is the process of calculating by means of symbols called numerals. It is the part of mathematics that concerns how to get answers to addition, subtraction, multiplication, and division problems. The word arithmetic comes from the Greek word arithmos, which means number.
Mathematicians use the term number to mean an idea having to do with the amount or quantity of a thing or things. They use numeral to mean a symbol that represents a number. For example, the numerals 6 and VI stand for the number also represented by the word six. But in everyday language, number is also used to mean numeral. The rest of this article uses number in the everyday way.
Many people use computers and calculators to do most of their arithmetic, but much arithmetic is still done with pencil and paper. Both methods of calculating rely on a numeration system (a system of counting and naming numbers) that determines the value of a digit by its position in a number.
The numeration system used by most people is called the decimal system, or base 10 system. In this system, a digit is any one of the symbols 0, 1, 2, 3, 4, 5, 6, 7, 8, and 9. Each position in a number with two or more digits has a value 10 times greater than the position to its right. And each position has a name that corresponds to its value. The positions, from right to left, are called the ones' position, the tens' position, the hundreds' position, the thousands' position, and so on. Each position has only one digit.
A computer or calculator does the actual arithmetic with another numeration system, the binary system. However, the user enters the problem in the decimal system, and the results are shown in the decimal system.
