Pump is a device that moves liquids and gases. Pumps are used in a variety of machines and other devices, including home heating systems, refrigerators, oil wells and water wells, and turbojet and automobile engines. The fluids that are moved by pumps range from air for inflating bicycle tires to liquid sodium and liquid potassium used for cooling nuclear reactors. Most pumps are made of steel or cast iron, but some of them are made of glass or plastic. Gas pumps are also called compressors, fans, or blowers.
The two main types of pumps are dynamic pumps and positive displacement pumps. Dynamic pumps maintain a steady flow of fluid. Positive displacement pumps, on the other hand, trap individual portions of fluid that are in an enclosed area before moving them along.
