An **integer** is simply a whole number like 0, 1, 2, 3 etc. An integer can be positive (i.e. above 0 on the number line e.g 77), negative (e.g. -4) or zero itself (which is neither positive nor negative).

Numbers which are not integers include decimals such as 4.38, fractions such as 1/2, surds such as \(\sqrt{2}\) and other irrational numbers such as pi.

An integer is a mathematical object most commonly used for counting and measuring.

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