An audio encoder compresses raw audio information -- from a CD, for example -- into a smaller digital audio file. Unlike other audio encoders like MP3 and AAC, FLAC uses lossless compression, meaning that FLAC files contain all the information that was present in the original audio. Because of this, a FLAC file is extremely high-fidelity, and is indistinguishable, or nearly so, from a CD containing the same audio, but it is able to compress the audio to approximately half its original size.
The VLC media player includes a built-in audio decoder that supports playing FLAC files. To play a FLAC file in VLC, click VLC's "Media" menu, select "Open File" and navigate to the FLAC file you want to play. Double-click the FLAC to load it into VLC. You can load multiple FLACs by holding the "Ctrl" key, clicking each FLAC you want to play, and then clicking the "Open" button. You can also drag and drop FLAC files from a Windows Explorer window into the VLC media player.
Besides the fact that FLAC encoding produces high-quality audio, the FLAC format has several advantages over other compression standards. Because a FLAC file contains all the data from the original audio waveform, you can re-encode a FLAC file into any desired format without losing audio quality. If you archive your music collection as FLACs, then you'll be able to convert it into whatever audio file format becomes popular in the future. The FLAC standard is open-source, meaning that users can use and modify it in any ways they desire. FLAC files can play on all common operating systems, including Windows, Mac and Linux.
Although VLC can play FLAC files, it cannot rip audio CDs into the FLAC format. If you want to archive your CD collection as FLACs that you can play in VLC, you'll need to use another program. The Exact Audio Copy CD ripping program and the Winamp media player can both convert CD audio to FLAC without any add-ons. Set the encoder to "FLAC" in the program's preferences. The dBpoweramp audio converter can also encode FLACs; however, you'll need to add a specially designed codec before you can do so.