This video covers checking the drain and circultaing pump in a GE style dishwasher. Many GE and other manufacturers use a single motor to drain and circulate. They usually have a check ball and flapper that help prevent water from going in the wrong direction. The motor will spin one way for drain and the other way to pump water to the circulating arms. They are easy to replace but depending on the age of your machine may not be worth repairing. Most drain and circulating pumps will last many years trouble free.
You might need to disable your pop up blocker to view videos