A wave dashing on the shore
A wave dashin on the shore in the Gulf o Santa Catalina

The sea, the warld ocean, or simply the ocean, is the connectit bouk o sauty watter that covers ower 70 percent o the Yird's surface. It moderates the Yird's climate an haes important roles in the watter cycle, carbon cycle, an nitrogen cycle. Altho the sea haes been travelled an explored syne auncient times, the scienteefic study o the sea—oceanografie—dates broadly frae the voyages o Captain James Cook who explored the Paceefic Ocean atween 1768 an 1779. In geografie, "sea" is uised in the names o smawer, pairtly laundlocked sections o the ocean, for example the Irish Sea, while "ocean" is uised in the names o the five lairgest sections, sic as the Paceefic Ocean.