What is CAD ?
CAD is an acronym for Computer Aided Design or Computer Assisted Drafting. CAD is commonly used in the practice of architecture, engineering and manufacturing to assist in the production of technical drawings and documents. Architectural CAD software facilitates the drawing/drafting of floor plans, elevations, sections, three-dimensional models and renderings. CAD files are "to-scale" and are fully editable by competent CAD users.
There are several CAD software packages available; each offering different levels of specialization, sophistication and cost. AutoCAD by Autodesk is the most recognizable CAD software in use today and the AutoCAD DWG file format is widely accepted as the defacto standard for sharing and distributing CAD documents. Other popular formats include DXF, DWF, DGN (Microstation) and PLN (ArchiCAD).
Although CAD is not generally intended for novice users, there are a number of free and fee-based "viewers" that allow you to open, navigate and print CAD files. Extreme Measures Inc. is a CAD services company that specializes in architectural drafting.