There are many types of air pumps, but some of the most popular are the hand-held pumps, the electric pumps, and the pump-in-the-bag pumps. The hand-held pumps are the most popular type because they are easy to use and can be carried around with you. They are also the most affordable. The electric pumps are the next most popular type. They are usually powered by electricity, and they can be used to pump air or water. The pump-in-the-bag pumps are the most advanced type. They are designed to be used with a pump-in-the-bag device, which is a device that helps you to pump the air out of the pump.