Snail is a common name which is applied to most of the members of the molluscan class Gastropoda that have coiled shells in the adult stage. When the word is used in its most general sense, it includes sea snails, land snails and freshwater snails. The word snail without any qualifier is however more often applied to land snails than to those from the sea or freshwater. Snail-like animals that naturally lack a shell, or have only an internal shell, are often called slugs, and land species that have only a very small shell (that they cannot retract into) are called semislugs.
the snail