Slugs and snails are both part of the same class of
gastropods. Gastropod comes from the Greek words gastros
(stomach) and podos (foot). Most gastropods live in water.
Snails and slugs are the only gastropods that can also be found
on land, but the majority of snails and slugs live in water.
The most obvious
difference between snails and slugs is snails have shells. Their
only other differences are in habitat and behavior. Without
those big shells to carry around, slugs can squeeze themselves
into many different habitats that snails cannot.
As they move along,
leave behind a slimy trail, called mucus. Snails and slugs make
mucus so that they can move on the ground and keep their bodies
from losing moisture to the dry soil beneath them. It also
protects them from being cut by sharp objects in the soil.
Snails and slugs can completely destroy gardens by eating plants
and fruits, including their roots, leaves, and stems. One
redeeming feature is that escargot, which is made from
land snails, tastes great.