Bay is a part of an ocean, a lake, or a similar body of water. A bay forms an indentation in the shoreline. It is bordered by headlands or capes. Bays are commonly produced when the water level of a body of water rises above the level of the adjacent land, submerging it. For example, Chesapeake Bay and other bays along the east coast of the United States were formed when huge glaciers melted more than 10,000 years ago. The melting caused the Atlantic Ocean to rise and flood its coastal area.
The capes or headlands that form the borders of a bay protect the shoreline within. They shield it from the powerful pounding of waves from the sea. The waves are concentrated on the capes or headlands. They are then spread out within the bay itself. Soil and other materials are washed away from these land formations. The action of the waves deposits these materials within the bay.
See also Estuary .