An integer is a whole number that can be positive, negative, or zero. It does not include fractions or decimals. For example, numbers like -3, 0, 7, and 42 are all integers. Integers are used in various everyday situations, such as counting objects or measuring temperature. In mathematics, integers are part of a larger set called the real numbers, which also includes fractions and irrational numbers. They are essential for basic arithmetic operations like addition, subtraction, multiplication, and division. Understanding integers is crucial for solving problems in math and science, making them a fundamental concept in education.