1, different body types: cuttlefish has a slightly rounded body and a short body length, while squid has a long cone shape. 2. Different colors: The skin color of cuttlefish is dark, and there will be some obvious spots, while the skin of squid is mostly purple or light purple. 3. The internal structure is different: the cuttlefish has a hard shell, while the squid has only a slender translucent soft inner shell.

Cuttlefish is an animal of the order Cephalopoda in mollusca. When cuttlefish meets a strong enemy, it will use "inkjet" as an escape method and wait for an opportunity to leave, so it has the name "squid" and so on. There are pigment vesicles in the skin, which will change color and size with the change of "mood". Cuttlefish will jump out of the sea and have amazing air flight ability. Like squid and octopus, they belong to marine mollusks, and none of them belong to fish.

Squid, also known as soft fish and squid, is an eye-opening suborder of Cephalopoda Sheath, a suborder of mollusca. The body is cone-shaped, pale with light brown spots, with a big head, touching feet 10 in front, and the fleshy fins at the tail end are triangular, often swimming in groups in the ocean about 20 meters deep.

Squid is a valuable seafood. The sex of squid fry is artificially controlled to change the characteristics of squid. From hatching to 10 month old, the weight of male squid can reach 700 grams, while that of female squid is only 300-400 grams. Therefore, experts are exploring to change most squid into males, which will greatly improve the output of squid.