A whole number is a number that is not a fraction or decimal. It includes all the positive numbers starting from zero, such as 0, 1, 2, 3, and so on. Whole numbers are used in everyday counting and measuring, making them essential in mathematics and daily life. Whole numbers do not include negative numbers or any parts of numbers, like 1/2 or 3.14. They are often represented on a number line, where each point corresponds to a whole number. Understanding whole numbers is the first step in learning more complex math concepts, such as addition, subtraction, and multiplication.