I am a developer for The XFree86 Project, Inc. a non-profit organization which produces X Window System servers for PCs running Unix. I also maintain the XFree86 FAQ.
If you have questions regarding XFree86, please send them to XFree86@XFree86.org. You'll almost certainly get a quicker response than if you send them directly to me.
Tcl is an embeddable and extensible scripting language for Unix (and lesser operating systems). Tk is an extension to Tcl for graphical interface programming.
See my Tcl/Tk page for pointers to more info, including the FAQ I maintain, regarding programming in Tcl.
If you are inside the Intel firewall, you can also see my internal home page for info related to my current projects.