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Squid are mollusks along with clams, mussels, limpets, and snails. The term Mollusca means soft-bodied. Squid are members of the class Cephalopoda. Cephalopod means "head-footed" and are named because their arms surround their mouths. Cephalopods are predators, feeding on smaller sea animals.

Squid are an excellent food source and are popular for eating all over the world. The squid has a large head and a relatively large brain. It has a naked body, with an interior skeleton made of cartilage. It is spherical or cigar-shaped, with two lateral fins. Around the mouth are eight sucker-bearing arms and two tentacles that can contract. The two tentacles have suction cups with hard hooks that are used to capture prey. The larger tentacles pass the prey to the shorter arms that hold the meal while it is devoured using its hard beak.

The large cone-shaped body part is called the mantle. Squids also have a small internal shell. Squid can swim very fast when needed by expelling water out of the mantel cavity moving by the reaction force of the water. Squid are the fastest swimming invertebrates (animals without backbones). Their speed can be compared to releasing air from an untied balloon. Squid also have ink sacs. The ink can be squirted into the water for camouflage when they need to escape from a predator. The ink forms a squid shape that confuses the predator.