About Music Files
You can download music files from Internet music sites, or "rip" music files from audio CDs to your computer. Music files that you transfer to your player must, however, be MP3 or WMA files if you want to play them back.
WMA files are music files that have lossy compression encoding, which means that some data is lost during compression. The standard bitrate for most WMA files is 128 kbps. Higher bitrates will result in better audio quality, but file sizes will be larger as a consequence.