A positive integer is a whole number greater than zero. These numbers include 1, 2, 3, 4, 5, and so on, extending infinitely. Positive integers are used in various everyday situations, such as counting objects, measuring quantities, and ranking items. In mathematics, positive integers are part of the set of natural numbers, which also includes zero in some definitions. They are fundamental in arithmetic operations like addition and multiplication, where the result is always another positive integer when combining two positive integers.