Numbers (for linguistic  learners)

1. Imaginary Numbers (negative under a square root, zero in the denominator)

2. Real Numbers (all numbers except imaginary)

2.1. Irrational (square root that is not a perfect square, pi, a decimal that never ends AND does not repeat)

2.2. Rational (all real numbers except irrational)

2.2.1. Integers (only whole numbers, can be negative or positive)