Elementary arithmetic

Elementary arithmetic is the simplified portion of arithmetic that includes the operations of addition, subtraction, multiplication, and division. It should not be confused with elementary function arithmetic.

Elementary arithmetic starts with the natural numbers and the written symbols (digits) that represent them. The process for combining a pair of these numbers with the four basic operations traditionally relies on memorized results for small values of numbers, including the contents of a multiplication table to assist with multiplication and division.

Elementary arithmetic also includes fractions and negative numbers, which can be represented on a number line.

Digits are the entire set of symbols used to represent numbers. In a particular numeral system, a single digit represents a different amount than any other digit, although the symbols in the same numeral system might vary between cultures.

In modern usage, the Arabic numerals are the most common set of symbols, and the most frequently used form of these digits is the Western style. Each single digit matches the following amounts:
0, zero. Used in the absence of objects to be counted. For example, a different way of saying "there are no sticks here", is to say "the number of sticks here is 0".
1, one. Applied to a single item. For example, here is one stick: I
2, two. Applied to a pair of items. Here are two sticks: I I
3, three. Applied to three items. Here are three sticks: I I I
4, four. Applied to four items. Here are four sticks: I I I  I
5, five. Applied to five items. Here are five sticks: I I I  I I
6, six. Applied to six items. Here are six sticks: I I I  I I I
7, seven. Applied to seven items. Here are seven sticks: I I I  I I I  I
8, eight. Applied to eight items. Here are eight sticks: I I I  I I I  I I
9, nine. Applied to nine items. Here are nine sticks: I I I  I I I  I I I

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