One of the numbers 1, 2, 3, ... (OEIS A000027), also called the counting numbers or natural
numbers. 0 is sometimes included in the list of "whole" numbers (Bourbaki
1968, Halmos 1974), but there seems to be no general agreement. Some authors also
interpret "whole number" to mean "a number having fractional
part of zero," making the whole numbers equivalent to the integers.
Due to lack of standard terminology, the following terms are recommended in preference to "counting number," "natural
number," and "whole number."