Grzegorczyk hierarchy

Grzegorczyk hierarchy is a way of organizing different kinds of numbers. There are five different kinds of numbers: Natural numbers, which are all numbers that start at 1 and go up (1, 2, 3, 4, 5, etc.); Integers, which are negative numbers and all the natural numbers (both -5 and 5); Rational numbers, which are numbers that can be written as a fraction (like 1/2); Real numbers, which are all rational numbers, plus irrational numbers like pi; and Transcendental numbers, which are numbers that cannot be written as a fraction and cannot be found by doing calculations (like pi). The Grzegorczyk hierarchy is a way of showing how these different kinds of numbers are related.