As Bernard points out software listens for the gaps, but as Geoff points out LP Ripper then lets you split the tracks wherever you want.

If you know there are 8 tracks on the album for instance you would choose 8 tracks and the software will guess where the splits are. If the tunes go into each other it will make it's best guess which will probably be wrong.

As he points out it then has a little playback device which allows you to listen to sections and decide where you want the splits to be; you then move the marker accordingly and the progam then produces 8 wav files according to the splits you have decided