Snails (gastropods) are molluscs without skeleton and include an estimated 100,000 different species worldwide. However, there are still differences between slugs and shell snails. They can move through a rhythmic tightening of muscles. The spiral-shaped house is made of lime, is constantly carried by the snail and serves as protection. In case of danger, snails slip into their house and close it with a lime lid. In case of damage, the house can be repaired again. Snails are common throughout the world and - depending on the species – get up to 10 years old.