Hi, I'm Jim Shields for About.com, and today I'm going to teach you about biomes. A biome is a large area on the earth that shares similar characteristics and life forms. The similar climate patterns and geographical features make it more suitable for certain types of plants and animals to thrive. Types of biomes include desert, tundra and rainforest. Climate plays an important role in defining a biome, and characteristics like humidity (arid versus humid), latitude (polar vs equatorial) or elevation are often included in descriptions of biomes. Sometimes, the word biome is confused with the word ecosystem. In fact, they are quite similar, but an ecosystem is usually much smaller and can be any set of organisms working together with their environment, such as a pond in the forest or a fallen oak tree, whereas a biome is a much larger area in which plants, animals and microorganisms have adapted to the specific conditions. Thanks for watching. To learn more about biology, visit us on the web at About.com.