What is Class Gastropoda in animal kingdom?

Snails and slugs are referred to as gastropods because of their characteristic body plan. "Gastro" is derived from the Greek word for "stomach," and "poda" refers to "foot." Together, they describe the stomach-footed body plan of snails and slugs. If you look at a snail or slug, you will see that this name is appropriate in that the visceral mass, much of which is the digestive tract, sits directly above the ventral foot.

Most of the species of gastropods are marine, but there are a significant number that inhabit freshwater and terrestrial habitats as well. Gastropods have one shell, as opposed to the bivalves. Some species, like slugs, and a marine group appropriately called nudibranchs, have lost their shells through evolution. Another feature unique to the Gastropoda is torsion. Their bodies develop in a twisted spiral because one side grows at a faster rate than the opposite side. The majority of gastropods have tentacles on their heads, which bear eyes.