What is Tcl?
Tcl is a simple-to-learn yet very powerful programming language. Its syntax is described in just a dozen rules, but it has all the features needed to rapidly create useful programs in almost any field of application - on a wide variety of international platforms. See more about Tcl at What is Tcl
What is Tk?
Tk is a graphical toolkit for Tcl. It allows you to develop graphical applications that run on Windows, Linux, MacOS X and many other platforms. And not just from Tcl - Tk can be used from many languages including C, Ruby, Perl, Python and Lua. See more about Tk at What is Tk
Tcl Community News
- The European OpenACS and Tcl/Tk conference will be in Vienna/Austria/Europe on July 16 & 17, 2026. See Tcl Conferences.
- 2026 North American Tcl/Tk Conference questionnaire If you are interested in attending a North American Tcl/Tk Conference in the fall of 2026, please consider taking our questionnaire.
- Tcl 9.0 Released on 26 Sept 2024! The Tcl Core Team is pleased to announce the release of Tcl 9.0 - a new major version of Tcl. When compared with the prior release Tcl 8.6 there are many new features to be enjoyed along with some incompatibilities to be considered. Concurrently released is version 9.0 of the Tk graphical toolkit. A summary of the most noteworthy changes in both Tcl 9.0 and Tk 9.0 can be found at the Tcl Developer Xchange .
- New TCT Members - the Tcl Core Team (TCT) is pleased to announce that Rolf Ade, Ashok Nadkarni and Harald Oehlmann have been elected to membership in the TCT, following the procedure described in TIP #0 https://core.tcl-lang.org/tips/doc/trunk/tip/0.md
- Another new TCT Member - The Tcl Core Team (TCT) is pleased to announce that Reinhard Max has been elected to membership in the TCT. As well as being a valuable member of the team, Reinhard will be a voice representing the needs of OS vendors/distributors within the TCT.
- Tcl/Tk 9.0.3 (13 November 2025) and 8.6.17 (15 August 2025) Released. The Tcl Core Team is pleased to announce the 9.0.3 and 8.6.17 releases of the Tcl dynamic language and the Tk toolkit. We would like to express our gratitude to all those who submit bug reports and patches. This information is invaluable in enabling us to identify and eliminate problems in the core. Sources are freely available as open source from the Tcl Developer Xchange .
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