When people think of digital audio, you think of MP3: The motion picture group’s layer-3.
But, there are other formats in town: AAC, WMA, MP-4 and many others.
One of the most interesting ones is Ogg Vorbis. Not only is it completely open source (and free of any restrictions), but it also sounds better. One of the best features is that it corrects a huge mistake that is implicit with MP3: Cannot handle gapless audio playback. So if you want to listen to that great live album or Pink Floyd CD, you have to absorb a little skip in the music. My personal tastes in music side towards the electronic/dance music realm. The whole art of it is in the seamless transition between one track to another. MP3 doesn’t handle this problem. Ogg does!
Try out ogg. You won’t go back.