Whole number is natural number

Answer 1

Although a few old books use "whole number" and "natural number" interchangeably, but common usage is that the natural numbers are

N = {1, 2, 3, 4, 5, 6, . . . }

and the whole numbers are

W = {0, 1, 2, 3, 4, 5, 6, . . . }.