3gp The 3GP file format and its associated filename extension .3gp is an audio, video, and text container developed by the 3rd generation partnership project. The target market for the 3gp file format is 3G enabled UMTS mobile phones through associated UMTS multimedia services. Though mobile devices operating on high speed networks are the intended hardware associated with playing .3gp files, many PC codec packs exist which grant compatibility for .3gp playback. The format has a basic profile in which files of this format do not reference any external media sources and support for audio, video, and text is limited to a single track.
flac The FLAC file format associated with the .flac filename extension refers to the FLAC audio encoding algorithm. FLAC is the acronym for Free Lossless Audio Codec. The algorithm is from the lossless audio compression family of formats for digital audio compression. It was developed by the Xiph.Org foundation, a non-profit organization that produces open and free to use multimedia formats, and had its initial release in 2001. Though there isn't widespread compatibility for the format as compared to similar formats such as MP3, the FLAC format enjoys some compatibility and support with in car and home stereo manufacturers as well audio playback software and portable audio devices.