Types of Numbers

Natural numbers N = {1,2,3...}. Whole numbers W = {0,1,2,3...}. Integers Z = {...-2,-1,0,1,2...}. Rational numbers Q = p/q where p,q are integers and q≠0. Irrational numbers: cannot be expressed as p/q (√2, √3, π, e). Real numbers R = Q ∪ Irrational.