Seafood is any sea animal that is served as food or is suitable for eating. This usually includes sea water animals, such as fish and shellfish (including mollusks, and crustaceans). These sea water animals are also collectively referred to as seafood.
From the earliest age of human civilization, seafood had been an important food source that can easily be hunted and gathered even by those lacking power or speed. A basket like trap were widely used to hunt fish in a river and a lake. Sometimes, fish was speared just as one would hunt a small animal. Ancient Egyptian civilization used the symbol of fish for counting large number and it was eaten both dried and fresh. It is looked over too often but the rise of ancient Greek and Roman civilization was in no small part to the abundant fish of Mediterranean Sea. Shellfish was a staple food in many locations and in Jomon period of Japan, amount of shellfish consumed and thrown away from that time is use to measure how many people lived in certain area.