OpenDesign_Specification_for_.dwg_files.pdf

1 Introduction Originating in the late 1970s, drawing files created with microcomputer-based computer-aided design software were saved with the .dwg extension. In the early 1980s, Autodesk® released AutoCAD® which eventually became the most used CAD software in the world and which used Autodesk’s undocumented and proprietary DWG™ file format (using the .dwg extension). The Open Design Specification for .dwg files serves AutoCAD’s undocumented and proprietary DWG file format. This specification includes DWG file format versions 13 up to and including version 2013. Further, the Open Design Specification for .dwg files serves the Teigha® software development platform of the Open Design Alliance. While our Open Design Specification for .dwg files is able to read and write .dwg files with excellent AutoCAD compatibility, we continue to work to improve our understanding of all the data in a .dwg file. If you find information which will help us to understand any unknown values, please contact us at http://www.opendesign.com/contact.