This is the Strawberry Snail, Trichia striolata a relatively small snail (about 10 mm wide), with a dull, finely sculptured round shell and dark body. The shell colour is variable, but this is the most common in my area. The shell has got an 'umbilicum' underneath, an open space between the shell worls. It genus name refers to the fact that the snail is hairy when young.
This is a similarly sized snail, the Girdled Snail. This angle shows the white keel that makes them easy to recognise. I have written about them before.