Current is the speed of movement in a water body. Current exists in rivers, lakes and oceans.
In a river, current is strongest in the narrowest and steepest parts of the system. These are usually found further upstream. Further downstream, the river broadens and sediments become smaller, so river current becomes weaker.
As a river meets the ocean, current is influenced by the tide. Tidal current is influenced by the height difference of high and low tides, which is determined by the moon.
Lake current is affected by the wind and the sun. The wind generally moves the upper portion of the lake water, while the sun can create movement in the entire lake by changing the water temperature at different layers.
Current is an important factor which anglers need to consider when planning their fishing outing. It controls your catch success more often than not.