The file extension flac is a file format for compressed music, much like the .mp3 format. The .flac file format can only be used by those who have installed the Free Lossless Audio Codec. Flac format is superior to mp3 format because their's no loss of quality and has a much better compression ratio. It's also easier for your PC to process than the mp3 file format.

Free lossless audio codec is free, no purchase is necessary, and it can be used by the public for any use they desire. It's encoding and decoding methods are not patented which will allow third parties to add-on to or upgrade the software without getting in legal trouble. FLAC is also open source, which means anyone can view and edit the source code.

The .flac decode algorithm is unique in that it uses integer arithmetic. By using integer arithmetic it makes it incredibly easy for CPUs to process .flac file and immediately decode it without too much strain on your PC. Almost all hardware, no matter how old, can easily decode the audio from a FLAC file in real-time. Since this file format is so advanced, it's likely it will replace the mp3 file format as more and more people catch on to it.