As you might have guessed from the title of this article, FLAC is an abbreviation of Free Lossless Audio Codec. The first word (“free”) should be pretty clear (it’s an open-source project), but what is a “lossless audio codec”? Well, the well-known MP3 format is an audio codec. It is used to compress raw audio data. MP3 is a so-called “lossy” codec, meaning that, for example, if you would convert a wav file to an mp3, and then convert the mp3 file back to wav, you won’t end up with the same audio data. MP3 reduces the quality of the audio while encoding. On the other hand, FLAC is “lossless”. If you would convert a wav file to a flac, and then convert the flac file back to wav, you will end up with exactly the same wav file. Nevertheless, a flac file is a lot smaller than a wav file.