FLAC
About
FLAC stands for Free Lossless Audio Codec. FLAC is an audio compression codec that is lossless. Unlike lossy codecs such as MP3 and Vorbis, it does not remove any information from the audio stream.
On January 29th, 2003, Xiphophorus (now called the Xiph.org Foundation) announced the incorporation of FLAC under their xiph.org banner, to go along with Ogg Vorbis, Ogg Theora, and Speex.
Comparisons
FLAC is distinguished from general lossless algorithms such as ZIP and gzip in that it is specifically designed for the efficient packing of audio data; while ZIP may compress a CD-quality audio file 20–40%, FLAC achieves compression rates of 30–70%.
While lossy codecs can achieve ratios of 80–90+%, they do this at the expense of discarding data from the original stream. Though FLAC uses a similar technique in its encoding process, it also adds "residual" data to allow the decoder to restore the original waveform flawlessly.
FLAC has become the preferred lossless format for trading live music online. It has a smaller file size than Shorten, and unlike MP3, it's lossless, which ensures the highest fidelity to the source material, which is important to live music traders.
FLAC compiles on many platforms: most Unices (including Linux, *BSD, Solaris, and Mac OS X), Windows, BeOS, and OS/2. There are build systems for autoconf/automake, MSVC, Watcom C, and Project Builder.