X11R7.7-RC1 is an Open Source version of the X Window System that supports Linux, BSD, Solaris, Cygwin and MacOS X on Intel and other platforms.
The X11R7.7-RC1 release has been produced by the many contributors to the X.Org community and members of the X.Org Foundation and includes code from the X Consortium, the Open Group and the XFree86® Project.