Jet pumps, also known as ejector pumps are devices that are capable of handling and transporting all forms of motive fluid such as steam, gas, and other liquids.
Jet pumps are used for a variety of applications involving the movement of water from a water source to a destination. If your home is supplied primarily by well water, you may need a jet pump to pull the water.
There has been a lot of interest in magnetic drive pumps lately. These pumps fall into the category of centrifugal pumps, though some are considered rotary positive displacement pumps. (A positive displacement pump makes a fluid move by trapping a fixed amount and forcing (displacing) that trapped volume into the discharge pipe.)