Throughout the history man is directly or indirectly influenced by the oceans. Oceans have many uses for man. 

1. Since early times man depended on oceans for food. Oceans are store houses for fish.

2. Ocean is a source of valuable minerals. Chlorine, Fluorine, Bromine and Iodine are found in oceans. 

3. Rock petroleum, Natural gas are extracted under oceans. 

4. Oceans are mined for mineral salt, sand, gravel manganese, copper, nickel etc. 

5. Some biological products of oceans are also commercially used. For example, pearls taken from oysters are used in jewellery. 

6. Shells and corals have been widely used as source of building material. 

7. Tides and waves are renewable energy sources. 

8. Oceans are sources of rainfall. 

9. Oceans act as international highways. 

10. Many great civilizations such as Greek civilization, Rome civilization all flourished on the banks of rivers and oceans.

There are many more uses for man from oceans. Hence we can say without oceans life of man is impossible.