Introduction to AutoCAD

AutoCAD is a suite of CAD software products for 2- and 3-dimensional design and drafting, developed and sold by Autodesk, Inc.. The original concept of AutoCAD in the 1980s was to promote customization and feature extensibility, and was what made it especially appealing to customers. Most contemporary CAD products at that time offered little if any customization capability and most were far more expensive.

Modern AutoCAD includes a full set of basic solid modeling and 3D tools, but lacks some of the more advanced capabilities of solid modeling applications. AutoCAD can be used as a platform for other products such as Bentley AutoPLANT and COADE CADWORX. AutoCAD is a vector graphics drawing program. It uses primitive entities — such as lines, polylines, circles, arcs, and text — as the foundation for more complex objects.

AutoCAD supports a number of application programming interfaces (APIs) for customization and automation. These include AutoLISP, Visual LISP, VBA, .NET and ObjectARX. ObjectARX is a C++ class library, which was also the base for products extending AutoCAD functionality to specific fields, to create products such as Autodesk Architectural Desktop, AutoCAD Electrical, or third-party AutoCAD-based applications.

AutoCAD's native file format, DWG, and to a lesser extent, its interchange file format, DXF, have become de facto standards for interchange of CAD data. AutoCAD in later years has adopted another file format known as DWF. These files allow selected DWG drawings to be compiled to one file. This allows distribution of the drawings to those without AutoCAD or similar packages. It also protects the drawings from manipulation by others as the drawings are rasterized inside the DWF file. DWF files can be viewed with a free program from Autodesk called "DWF Viewer" - this program allows users to both view and print DWF files. Another advantage of DWF files is that a large number of drawings can be compiled to a single DWF and be of a very small to reasonble file size for electronic distribution. In 2006, Autodesk estimated the number of active DWG files to be in excess of one billion. In the past, Autodesk has estimated the total number of DWG files in existence to be more than three billion.

AutoCAD currently runs exclusively on Microsoft desktop operating systems. Versions for Unix and Macintosh were released in the 1980s and 1990s, but these were later dropped. AutoCAD can run on an emulator or compatibility layer like Virtual PC or Wine, keeping in mind the performance issues that can arise when working with 3-dimensional objects or large drawings. AutoCAD exists in 14 language localizations, including many European and Asian languages.