What separates whole numbers from parts of a whole?

Whole numbers are non-negative integers that include zero and do not contain any fractional or decimal components, such as 0, 1, 2, 3, and so on. In contrast, parts of a whole, or fractions, represent segments of a quantity and can include numbers less than one, like 1/2, 3/4, or 0.25. The key distinction lies in the fact that whole numbers count complete units, while parts of a whole express divisions of those units.