Tcl (Tool Command Language) is used by over half a million developers worldwide and has become a critical component in thousands of corporations. It has a simple and programmable syntax and can be either used as a standalone application or embedded in application programs. Best of all, Tcl is open source so it's completely free.

Tk is a graphical user interface toolkit that makes it possible to create powerful GUIs incredibly quickly. It proved so popular that it now ships with all distributions of Tcl.

Tcl and Tk were created and developed by John Ousterhout. Developers all over the world followed his example and built their own Tcl extensions. Today, there are hundreds of Tcl extensions for all manner of applications. We have cataloged hundreds of of these contributions, which you can find listed under our