When the waves attack a rock- form from two opposite sides, it produces a hollow bridge called Sea Arch.

Continued erosion, under the attack of the wave, can result in the total collapse of an arch the seaward portion of headland will remain as an isolated pillar called stack The stack is gradually eroded, leaving behind only the stump

A beach is a landform that's a narrow strip of loose particles along the coast of a body of water. Beaches are created by the accumulation of sediment, which is carried by waves and deposited on the shore.