Windows Media Audio is a format engineered by Microsoft and touted as a better compressed file format than MP3. Microsoft asserts that you can store twice the amount of music in the same space if you use WMA files instead of MP3 files. They assert that a WMA file with a bit rate of 64kbps sounds equivalent to an MP3 with a 128kbps bit rate.You'll have to decide for yourself if they're right. Arguments about which file format is best abound on the Internet, and numerous people have put all sorts of audio file formats through their paces looking for the true "best." I've included, on your CD, links to several studies.If you do decide to use WMA, you'll be happy to know that it's very easy. Simply use the DirectShow MP3 streaming code! Out of the box, it will play WMA files.I just wanted to mention it here in case you looked through the table of contents and came straight here. The knowledge you seek is mere pages behind where you now read!