The octopus is a soft-bodied, eight-limbed mollusc. Around 300 species are recognized, and the order is grouped within the class Cephalopoda. The arms and sometimes other body parts are prepared in various ways, often varying by species and/or geography.

Octopus is a common ingredient in Japanese cuisine. It says Japanese has eaten since ancient times. Madako (East Asian Common Octopus) and Mizudako (Giant Pacific octopus) are good for ingredient. Octopus, like nearly all seafood, is lean and low in calories.