Start and stop markers can be placed either end of each file and gaps inserted between tracks. You can also crossfade tracks into each other so there are no gaps, but as long as you have inserted markers the finished CD will still play continuously or you can still skip from track to track.
The best feature for me of this software is allowing you to match the volumes of each individual track to one another. By simply clicking an icon and holding down the mouse key you can raise or lower the volume of any individual track without affecting any others in the montage. You can tweak away until your hears content, getting levels right until you're completely happy and the sound is balanced across the whole of the finished CD. An obvious but great tool.
There are so many more features I could waffle on about such as track naming, fade in/outs, ISRC codes and so on, but just to get your basic CD sounding professional this is a great piece of software.
There are numerous video tutorials on Youtube for Wavelab and I would recommend checking them out. As the old saying goes - Knowledge is Power! Best of Luck...