Natural numbers are the counting
numbers and they are always positive.
The set of natural numbers begin at 1 and go on indefinitely.
The natural numbers look like {1, 2, 3, 4, 5, ...}.
When we include 0 in the set of natural numbers, the new set,
{0, 1, 2, 3, 4, ...} is called the set of whole numbers.
Notice that all natural numbers are
included within the set of whole numbers.
We can represent the relationship between these
two sets of numbers using a diagram.
The bigger circle below represents the set of whole numbers
and all natural numbers will appear within the set of whole numbers.
In summary, natural numbers are the same as whole numbers except for the fact that whole numbers include 0.