The term "sea slug" refers to a group of marine gastropod mollusks that are diverse in shape, size, and color. These fascinating creatures range from tiny to large, from colorful to transparent, and from harmless to venomous. There are numerous synonyms for the term "sea slug," including nudibranch, sea hare, sea snail, and sea worm. Nudibranchs are known for their striking colors, while sea hares are identified by their elongated bodies. Sea snails have shells, while sea worms lack them. Regardless of their name, sea slugs play important roles in marine ecosystems by helping to control populations of algae and other organisms.