seven seas?

[crisgal]

are there really seven seas?

what's the difference between an ocean and a sea?

[Clanad]

The words ocean and sea are used interchangeably, yet a sea is a body of water that is much smaller than an ocean. The term "seven seas" was used by the Mohammedan explorers before the 15th century. The "seven seas" included the Mediterranean Sea, Red Sea, East African Sea, West African Sea, and China Sea, the Persian Gulf, and the Indian Ocean. In modern times, it has become common to divide the world's oceans into seven parts to retain this legendary number. The popular and accepted division today is the Arctic, North Atlantic, South Atlantic, North Pacific, South Pacific, Indian and Antarctic Oceans...(with thanks to Ocean Trivia)