There is only one World (or global) Ocean however the vast body of water that covers 71 percent of the Earth is geographically divided into distinct named regions.
The boundaries between these regions have evolved over time for a variety of historical, cultural, geographical, and scientific reasons.
Historically, there are four named oceans:
(1) the Atlantic ocean
(2) the Pacific ocean
(3) the Indian ocean
(4) the Arctic ocean
However, most countries - including the United States - now recognize the Southern (Antarctic) as the fifth ocean.
The Pacific, Atlantic, and Indian are known as the three major oceans.
East Siberian Sea
East China Sea
Gulf of Alaska
Sea of Japan
Sea of Okhotsk
South China Sea
This is not a complete list.
Gulf of Guinea
Bay of Bengal
The continental shelf is an underwater landmass which extends from a continent, resulting in an area of relatively shallow water known as a shelf sea.
The continental margin, between the continental shelf and the abyssal plain, comprises a steep continental slope followed by the flatter continental rise.
The World Ocean modified from: http://oceanservice.noaa.gov/facts/howmanyoceans.html
The global continental shelf modified from :https://en.wikipedia.org/wiki/Continental_shelf