Explanation:
The world has five recognized oceans, as defined by the International Hydrographic Organization (IHO):
Pacific Ocean (Largest and deepest)
Atlantic Ocean (S-shaped, separates Americas from Europe/Africa)
Indian Ocean (Bordered by Asia, Africa, and Australia)
Southern (Antarctic) Ocean (Encircles Antarctica, recognized since 2000)
Arctic Ocean (Smallest, around the North Pole)
Mnemonic:
"P.A.I.S.A." (Pacific, Atlantic, Indian, Southern, Arctic).
Ranked by size from largest to smallest:
Pacific > Atlantic > Indian > Southern > Arctic