Geography is the study of the physical characteristics of the Earth. It comes from the Greek words "geo" meaning Earth and "graphia" meaning description. There are five main themes in geography: location, place, region, interaction between humans and the environment, and movement. Location refers to where places are located either through absolute coordinates or relative to other locations. Place describes the distinguishing physical and human characteristics of an area. Region is a part of the world defined by similar physical or cultural traits. Interaction examines the relationship between humans and their surrounding environment. Movement refers to the transfer of people, items, and natural phenomena between different locations.