There are several nice sites which describe the commonly known characteristics of these humble creatures, like:
--but what tweeks my curiosity is the unusual qualities of their slime (which is being looked at for a medical adhesive), their adaptability, and their (apparent) ability to simply know the locations of food and water:
This has happened several times on our porches.
What gets to me is that straight line of slow, purposeful travel, even to climb up the side of a box we put on the porch --in hopes of defeating the slug's food homing "system".
How do they do that!?!?
Maybe the Wiki will eventually tell us:
(Goodness -!- but this is a short web page.)