The currents in the oceans are originated due to combined effects of several factors acting internally as well as externally. The factors, in fact, controlling the origin and other characteristics of ocean waters, rotational mechanism of the earth, external factors or atmospheric factors, topographic characteristics of the coasts and ocean basins. Usually the direction of the currents is guided by the direction of the prevailing winds. The ocean currents, like the circulation of planetary winds, are deflected by the rotation of the earth according to Ferrel’s Law. Hence, the currents of the northern hemisphere are deflected towards the right and those in the southern hemisphere to the left. The shape of the landmasses helps in guiding the direction of the currents. The speed of the current in mid ocean is slow and it is speedy in coastal region. Currents of warm water flow along the surface as surface currents and cold water currents flow along the ocean bed as bottom current. The movement of ocean water from one part to another takes place due to effects of the earth’s rotation, wind difference, salinity and density of sea water, etc. The movement of ocean water is called ocean current. It is to be noted that the waves are not currents because the movement of water does not take place in waves. Ocean currents are more powerful of all the dynamics of oceanic waters because these drive oceanic water for thousands of kilometres away. The forward movement of surface water of the oceans under the influence of prevailing winds is called drift whereas the ocean current involves the movement of oceanic water in a definite direction with greater velocity. Ocean stream involves movement of larger mass of ocean water like big rivers.