natural numbers are counting numbers like 1,2,3,4,5...
this set does not include negative numbers or 0
whole numbers are natual numbers but including 0
integers are whole numbers and also negative numbers
rational numbers are numbers that can be written in form a/b where b≠0
irrational numbers can't be written in form a/b, examples are like pi
real numbers are all of the abovee and more
26 belongs to the natural numbers set