AutoCAD is a software application for both 2D and 3D computer-aided design (CAD) and drafting — available since 1982 as a desktop application and since 2010 as a mobile web- and cloud-based app, currently marketed as Autocad 360.
AutoCAD is used across a range of industries, including architects, project managers and engineers, among other professions. AutoCAD's DWG file format has been widely adopted. More Info »
AutoCAD offers an extensive API for extensions and custom objects, a modern 3D rendering engine and modeling tools, and several import and export options.
A free 30-day trial version is available with registration.