FLAC, or Free Lossless Audio Codec, is a compression technique for digital audio that provides a bit-perfect copy of a CD's WAV audio while decreasing the file size by half. Yes, not as small as MP3 (or AAC, or WMA) but those formats REMOVE data that it "thinks" is inaudible in order to get the file size down. That is referred to as a "lossy" codec.

This is why I will never purchase from iTunes (except the damn 4-song exclusive Roger Clyne and the Peacemakers release) until I can get lossless tracks. Apple and Microsoft DO have "Apple lossless" and "WMA Lossless" but again, tied to one platform. FLAC is open source and works on Mac, PC, Linux.

Why bother? I like sound quality.