Beach

A beach is a landform along a body of water made up of loose particles such as sand, gravel and pebbles, or biological material like mollusk shells and coralline algae fragments. Beaches form through wave action, as waves and currents move sand and other loose sediment onto and along the shoreline. The sand itself comes from several sources, including the erosion of offshore rocks and headlands and the breakdown of coral reefs, and even fish that graze algae off coral and rock and excrete the resulting mineral particles as sand. A beach composition and appearance depend on local geology and wave energy, and both human activity and climate change are now altering the natural processes that build and maintain beaches.