This document defines different types of numbers and rational numbers. It explains that rational numbers can be expressed as a ratio of two integers in the form p/q, where p and q are integers and q is not zero. Examples of rational numbers include 1/2, 4/3, and 5/7. The document also discusses how rational numbers can be represented on a number line between integers, with an example given between 0 and 1. Properties of rational numbers are listed, including closure, commutative, and associative properties as well as additive identity and inverse.