This document provides a basic overview of zoology, listing different categories of animals that inhabit Earth including their environments. It discusses the major kingdoms that animals belong to such as amphibia, aves, mammalia, arthropoda, mollusca, and reptilia. Examples are given for each kingdom including tree frogs, owls, tigers, spiders, snails, and tortoises. It also notes that invertebrates make up the largest percentage of species on Earth and lists nematodes, spiders, birds, bats, moles, camels, sheep, tigers, fish, and sharks as examples of vertebrate and invertebrate animals in different habitats.