Octopus belong to the Cephalopoda class, which also includes species such as squid, cuttlefish and nautilus. More than 300 different types of octopus exist. They can be found in oceans all over the world in both shallow and deep water. The most common octopus people are generally interested in are the common Atlantic octopus, giant Pacific octopus, blue ringed octopus and the reef octopus.
