Beaches are the dumping grounds for the seas. Winds and tides struck against rocky coasts, taking out fragments from them.
Over millions of years, this process continues, making rocks crumble to minute grains. This continuous struggle between the sea and the rocks result in the formation of sand.
The waves and ocean currents carry off the very fine particles. As the waves of the sea calm down, they allow the sand to settle at the bottom.
With the passage of time, the waves spread it out on the shore to form the beach. Rivers also bring down a large quantity of sand from the mountains, when they join the sea.
Below Beach info from Wikipedia (Read More):-
A beach is a geological landform along the shoreline of a body of water. It usually consists of loose particles which are often composed of rock, such as sand, gravel, shingle, pebbles, or cobble. The particles of which the beach is composed can sometimes instead have biological origins, such as shell fragments or coralline algae fragments.
Beaches often occur along coastal areas where wave or current action deposits and reworks sediments.
Although the seashore is most commonly associated with the word "beach", beaches are not only found by the sea or ocean: beaches also occur at the margin of the land along lakes and rivers where sediments are reworked or deposited.
http://en.wikipedia.org/wiki/Beach
