What is the main reason for ocean surface currents?

Ocean currents represent the movement of the surface layer of water. The reason for the formation of constant currents lies in the constant winds of the Earth. So, an example can be called the current of the Western winds in the Southern Hemisphere, which passes in temperate latitudes and is directed from the west to the east. In tropical latitudes, trade winds are formed under the influence of trade winds blowing between the tropics towards the equator from the southeast in the southern hemisphere, from the northeast in the northern hemisphere.