Lobsters are marine crustaceans belonging to the family Nephropidae. They are easily recognizable by their elongated bodies, muscular tails, and large claws, which they use for defense and capturing prey. Lobsters are found in oceans around the world, typically inhabiting rocky, sandy, or muddy bottoms from the shoreline to depths of more than 500 meters (1,640 feet).

Lobsters have a hard exoskeleton, which they must periodically shed and replace in a process called molting in order to grow. This process makes them vulnerable for a short period until their new shell hardens. Their bodies are divided into two main parts: the cephalothorax, which includes the head and thorax, and the abdomen, which is commonly referred to as the tail.

One of the most striking features of lobsters is their two different types of claws. The larger crusher claw is used to break open hard-shelled prey like mollusks, while the smaller pincer claw is used for cutting and tearing softer food. In addition to these claws, lobsters have several pairs of walking legs and two long antennae that they use to sense their environment.

Lobsters are omnivorous scavengers and predators, feeding on a wide variety of marine organisms, including fish, mollusks, other crustaceans, and even plant matter. They are primarily nocturnal, hiding in crevices and burrows during the day and emerging at night to forage for food.

Lobsters have blue blood due to the presence of hemocyanin, a copper-based molecule that carries oxygen, unlike the iron-based hemoglobin in human blood, which is red. Another fascinating aspect of lobsters is their ability to regenerate lost limbs, including claws, legs, and antennae, although this process can take several molting cycles to complete.

Lobsters can live for a long time, often exceeding 50 years, and some scientists believe they may not show typical signs of aging, potentially living indefinitely under ideal conditions. Their long lifespan, combined with their complex molting process and regenerative abilities, make them one of the most intriguing creatures in the marine world.

Economically, lobsters are highly valued as a seafood delicacy, particularly the American lobster (Homarus americanus) and the European lobster (Homarus gammarus). They are caught using lobster traps and are a significant part of the fishing industry in many coastal regions.