This was a fairly quick and dirty introduction by example to creating graphical user interfaces for command line applications with Tcl and Tk. In addition to the language's basic syntax, we learned about procedures, several of the basic widget sets, progam control flow, some of Tcl's logical operators, and the basics of how to insert text into a text widget.
The simplicty of Tcl's syntax makes it a very easy language to learn and to build in. Our final example was built with less than 40 lines of code. If you want to go beyond the basics described here, the gridded window provides a more advanced mechanism for building window geometries than the packer that we used for this tutorial. Also, Tcl can be used for more than simply scripting graphical interfaces. For example, Don Libes' expect programming language, which provides facilities for constructing a programmed dialogue with interactive programs, was written in Tcl and C. The next section discusses where to go next for more resources on Tcl and Tk.