The méduse, commonly known as the jellyfish, is a gelatinous marine creature found in oceans worldwide. They have a simple body structure, consisting of a bell-shaped umbrella and tentacles that can sting. Jellyfish are part of the phylum Cnidaria, which also includes corals and sea anemones. Jellyfish are known for their unique ability to drift with ocean currents. They primarily feed on small fish, plankton, and other marine organisms. Some species can be bioluminescent, producing light in dark waters. Despite their beauty, jellyfish stings can be painful and, in some cases, dangerous to humans.