Cardinal numbers are the numbers used to count objects or indicate quantity. They answer the question "how many?" For example, in the phrase "three apples," the word "three" is a cardinal number that tells us the quantity of apples being referred to. Cardinal numbers include 0, 1, 2, 3, and so on. These numbers are different from ordinal numbers, which indicate position or order, such as first, second, or third. Cardinal numbers are fundamental in mathematics and everyday life, helping us quantify items, perform calculations, and understand basic concepts of quantity and counting.