Cuttlefish or cuttles are marine molluscs of the order Sepiida. They belong to the class Cephalopoda, which also includes squid, octopuses, and nautiluses. Cuttlefish have a unique internal shell, the cuttlebone. Cuttlefish has a flat, oval shaped body, covered by the skin that serves for swimming. The body continues to the head with 8 short and 2 slightly longer arms. On each arm there are 5 to 6 major adrenals. Her eyes are large, and her pupils have a rounded letter w. The color is very variable. By color and body nabing, it is ideally adapted to the environment.

On the head there are arms to catch food, and these are 10. Eight equal with adhesives (adhesive organs) while the remaining two are used to capture the plunder and are considerably longer than the others. They are wrapped in the knife under their eyes, and at the time of the hunt they are able to kick them off at a high speed.

Running away from the enemy the cuttlefish produces a special type of ink, that ink mixed with water becomes an opaque cloud and so allows the cuttlefish to escape. Plunder is easily to catch because cuttlefish is difficult to notice, not only because of the variable color, but also because of the ability to graft skin, adjusting the texture of the environment. Interestingly, it has three hearts, one of which is a pump, and of course it pumps blue blood.