Ocean currents fall into two main categories

The topography of the ocean floor and the shoreline modifies those motions,causing currents to speed up,slow down, or change direction.Ocean currents fall into two main categories:surface currents and deep ocean currents.Surface currents control the motion of the top 10 percent of the ocean water,while deep-ocean currents mobilize the other 90 percent.Though they have different causes,surface and deep ocean currents influence each other in an intricate dance that keeps the entire ocean moving.