The four types of erosion are sheet erosion, rill erosion, gully erosion and splash erosion. Erosion is defined as the withering away of the surface of land by either rain or irrigation water, wind or ice.
Sheet erosion occurs when a very thin layer of surface dirt or soil is removed from a large area. The result of rill erosion is a set of small channels viewed on a slope that are caused by running water. Gully erosion exists when larger and wider channels are cut out of slopes by running water. Splash erosion is caused by the movement of splashing water.