MPlayer
MPlayer (from The Movie Player) is a cross-platform media player released under GPLv2. The recommended way to install is to compile source code from SVN, though builds (binaries) are available from third parties. Numerous skins are available—by default there is no skin, meaning no graphical user interface.
Work on the project began in 2000 and is still actively developed as of 2019, with extensive documentation and support lists.
There are common elements between VLC media player and MPlayer, and the two projects share at least one contributor (Diego Biurrun). VLC reuses the MPlayer swscale software scaler library (included with FFmpeg) and MPlayer can be extended with the VideoLAN x264 library. libdvdnav and libdvdcss were included with MPlayer until 1.2. VLC and MPlayer both currently use FFmpeg to support many codecs, and work is done to keep MPlayer, VLC and FFmpeg codec support in sync.