Xorg
From Linuxhelp Wiki
aceleltlicro The X.Org Foundation is a group that develops a free implementation of the X11 protocol. In eary 2004, the XFree86 project team alterted their licensing for their implementation of X11 which many people considered to be non-free and incompatible with the GPL, because of this, many major distributions opted to either freeze their release of XFree86 to the last release before the license change (v4.3.x), or completly remove it from their distribution. The original codebase of Xorg is from the XFree86 repository just before the license change.
Since the split from the XFree86 tree, there have been 4 releases; X11R6.7, X11R6.8, X11R6.8.1, and X11R6.8.2. Xorg still maintains the same support that XFree86 did because it is essentially the same codebase, and even offers some additional features not available in XFree86. The only real change that the end user will see is the new configuration file xorg.conf which is basically just a renamed XF86Config.
