X Window System Version 11 Release 6.7.0
X11R6.7.0 is an Open Source version of the X Window System that supports
many UNIX(R) and UNIX-like operating systems (such as Linux, FreeBSD,
NetBSD, OpenBSD and Solaris x86) on Intel and other platforms. This
version is compatible with X11R6.6, and is based on the XFree86 4.4.0RC2 code base, which,
in turn was based on the X Consortium X11R6.6 and earlier sample implementations.