There are many different ways we can classify numbers. In fact,
many of the classifications are subsets of other classifications. The following
are depictions of how the classifications relate.

Natural Numbers 
Whole Numbers 
Integers 
Rationals 
Irrationals 
Examples 
1, 2, 3, 4,... 
0, 1, 2, 3, 4,... 
…, 3, 2, 1, 0, 1, 2, 3, ... 
1/4, 6/5, 0.125, 3.272727 
, 2.345678... 
What's new 

0 
Opposites of natural numbers 
Fractions, repeating and terminating
decimals 
nonterminating
decimals 
Together the rationals and irrationals form a larger set of
numbers called the Real Numbers.
