Purpose: detail some of the ways that Tcl can be used within the client's WWW browser.
There are several ways to do this.
There was, in the past, a package called the Tcl/Tk Tclet Plugin, which allowed one to safely display data in the browser. This code is now on Sourceforge.net and users can sign up for the project to help debug and maintain it.
There was some work by Mike Doyle (MDD) and Hatte Schoeder on writing interactive web applications - they actually published a book on the subject. The company for which they worked, Eolas, has a patent on the idea of software being downloaded into the browser for execution I believe.
There is also some research that was presented at the last two or three Tcl workshops relating to Tk applications running safely over the WWW but not dependant on the plugin.
There are often questions about the status of the plugin code. Unfortunately no one appears to be interested enough in the code to keep it up to date. And with the latest versions of Microsoft Internet Explorer no longer supporting plugins, it becomes less and less relevant.
Note that an ActiveX Tcl plugin was mentioned in comp.lang.tcl within the past yr or so - don't know whether that info made it to the wiki yet or not. But as was said by others, it is so sad that this package never was really picked up on by the community for support.