Phylum Mollusca is a group of invertebrate animals which includes the snails, clams, squid, and octopuses. This phylum can be described by a few synonyms such as Mollusks, Malacology, and Molluscum. Mollusks are soft-bodied animals, often with a hard protective shell, that are found in marine and terrestrial habitats. Malacology is the study of Mollusks including their biology, ecology, morphology, and systematics. Molluscum is the medical term used to describe a type of skin infection caused by a virus that affects humans. Overall, Phylum Mollusca is a diverse and fascinating group of animals that play important ecological and economic roles in various ecosystems.