Where I grew up, in the Midwest, slugs were a garden problem. They'd hole your tomatoes, and eat the leaves of about everything else. These little black shell-less terrors got perhaps an inch long and were less than 1/4" across.
Here in the Pacific Northwest, they grow the slugs bigger. Seriously people, you have NO IDEA. Here, a slug 6-8" long is the norm, and these guys (and gals? how do you tell?) are 3/4" across. And, no they are not black. Most are green with random dark spots, and there is a second kind that is brown. Stepping on one is seriously dangerous - as dangerous as stepping on a banana peel... but way more disgusting.
And they can swallow your tomatoes whole.