The lobster (homarus) is a crustacean and belongs to its own family, Nephropidae sometimes referred to as Homaridae. There are several types of lobster including the spiny and squat lobsters but most people are referring to the clawed lobster when they use the generic term "lobster." The clawed lobster is at the heart of a global seafood industry which produces billions in profits annually.

Clawed lobsters are arthropods (exoskeleton and segmented body) and invertebrates and have a hard exterior shell and soft interior. They consist of a segmented body with ten legs. The two front legs are shaped like claws and used for defense and hunting prey. Lobsters have very bad eyesight but are extremely agile swimmers and are very flexible.

Lobsters molt or shed their outer shell which they sometimes eat. After molting many types of lobster change the color of their shell. Unlike most species, lobsters have blue rather than red blood. Their blood contains a high concentration of copper rather than a high concentration of iron.

An average clawed lobster grows to a maximum of 20 inches in length. They usually move by walking slowly along the ocean floor. When in danger, they swim backwards very fast at a rate of 11 miles per hour. Lobsters do not lose vitality or strength as they age due to an enzyme they possess that repairs their DNA. If a lobster is not attacked, inured or captured by fisherman their lifespan is indefinite.

The boiling of live lobsters for food remains a controversial issue and in some places, the practice has been banned. The debate continues as to whether or not the lobster suffers during the boiling process.