There are a variety of Automatic pool cleaners and they are motivated in different ways However generally they can be put int several category's. Suction side bottom and surface cleaners these are connected into the suction of the pool pump and come on when the suction starts and pressure side cleaners which work by utilizing a venturi system for trapping larger particles like leaves seeds blowing the fine dust back up into the water to be sucked into the static skimmer. In the later category there is also the presure side cleaner that has a pump dedicated to it.