Questions about Computer Aided Design software developed by Autodesk; used mainly in engineering and architecture environments. Since engineering is out of scope you need to make sure that your question is related to graphic design.

AutoCAD is a commercial software application for 2D and 3D computer-aided design (CAD) and drafting. AutoCAD is used across a wide range of industries, by architects, project managers, engineers, designers, and other professionals.

Source: http://en.wikipedia.org/wiki/AutoCAD