The WAV format is a standard format for storage audio files, for both Microsoft and IBM. This format stores raw, noncompressed audio, and is compatible with majority operating systems. The MP3 format is a compressed audio format used by much personal numerical audio devices (MP3 players).
The Blade utility is an opened source order line utility to convert WAV files to the MP3 format. Temerity and WAV2MP3 are opened source graph programs that use the Blade libraries to convert the audio files.