A pump's a device used to move fluids, such as gases, liquids or slurries. A pump displaces a volume by physical or mechanical action. One common misconception about pumps's the thought that they create pressure. Pumps alone don't create pressure; they only displace fluid, causing a flow. Adding resistance to flow causes pressure. Pumps fall into two major groups: positive displacement pumps and rotodynamic pumps. Their names describe the method for moving a fluid. Positive displacement pumps… (More on Pump)