DWG ("drawing") is a file format used for storing two and three dimensional design data and metadata.
It is the native format for several CAD packages including AutoCAD,
IntelliCAD (and its variants) and Caddie. In addition, DWG is supported non-natively by
many other CAD applications. The .bak (drawing backup), .dws (drawing standards), .dwt (drawing template)
and .sv$ (temporary automatic save) files are also DWG files.