CAD , short for computer-aided design, computer-assisted-design, computer-aided drafting, or computer-assisted drafting, plays a special role in the history of Tcl, as JO created Tcl to meet the need for a reusable scripting language that could be deployed as a component part of the CAD program he was developing at the time.

See Also

CAD software history

CAD Systems Using Tcl

The most powerful/mature open-source CAD system that employs Tcl.
Contains one of the most powerful/mature closed-source high-end CAD modules on the planet. Its CAM module, also known as NX CAM employs Tcl.
A 2D CAD program with rudimentary support for 2.5D GCode generation..


John Ousterhout originally created Tcl for CAD software used to perform 2D (two-dimensional) layout of IC and PCB designs in the electronics industry (although he was of course in the academic world at the time). At the time Tcl was created, most PCB and IC CAD software was focused on simplifying the designer's job by ensuring that necessary manufacturing tolerances etc. were maintained in the layout and then producing drawings for producing etching plates or directly driving milling machines which produced the master etching plates.

A useful history of CAD software is available at , although at this time the history is unfortunately confined to the mechanical CAD world. Any comments and corrections will be appreciated and the site shortly intends to add a Wiki to allow additions to be freely made to the existing material.