The audio files are provided in three formats: MIDI, RealAudio and MP3.
The MIDI (Musical Instrument Digital Interface) files were generated directly from the sheet music using Encore. They contain just the melody without any accompaniment. MIDI files are very small because they are simply a series of binary codes that tell your computer's sound card what sounds to make. To play a MIDI file you will need a browser plug-in such as Crescendo from LiveUpdate or QuickTime from Apple Computer.
The RealAudio files were created directly from the master studio recordings. To hear the RealAudio files you will need the free RealPlayer from RealNetworks. With the RealAudio streaming file format and RealPlayer you will be able to hear the music instantly without waiting for the whole file to download.
MP3 is short for MPEG-1 Audio Layer 3 (Moving Pictures Expert Group), a format for storing digital audio. It uses an advanced type of audio compression which reduces the filesize to less than a tenth of the original with little reduction in quality. To hear the MP3 files you will need to install one of these MP3 Players or
QuickTime 4 from Apple Computer.
For more information on MP3 check out the site