Up until now, you've been working with

The Natural Numbers:

Natural Numbers = { 1, 2, 3, 4, ... }
 

The Whole Numbers:

Whole Numbers = { 0, 1, 2, 3, 4, ... }
 

The Positive Numbers:

Positive Numbers = All numbers greater than 0

These are all of the natural numbers and all the numbers in between (including between 0 and 1).