Bay is a body of water that is partly surrounded by land and has a wide opening to a larger body of water. Bays often have calm waters because the land around them provides protection. They can vary in size from small to very large. Bays are often shaped like a curve or a wide inlet.

Bays are found along coastlines around the world, such as the Bay of Bengal in Asia. They formed over long periods through natural processes. Bays are often used by humans for harbors, fishing, and settlement. They are important parts of coastal environments.