This document summarizes how animals can be classified based on various characteristics. It describes how animals can be categorized as vertebrates or invertebrates based on whether they have backbones. It also discusses how animals differ in their appearance, habitat, locomotion, diet as herbivores, carnivores or omnivores, and reproductive strategies of viviparous or oviparous birth. The document provides examples of different types of animals to illustrate these various classification methods.