Topography is the science of measuring the earth and its features, and of making maps, charts and plans to show them. These features may be natural, such as plains, hills, mountains, lakes, streams, rocks or forests. They may also be man-made, such as paths, roads, buildings, villages or fish ponds. A topographical map can also show the slope of the ground. It can show not only which places are high and which are low, but also how steep the land is between high and low points.