The extension DWG derives from Drawing and is a file format of AutoDesk AutoCAD. It contains the design data for 2D or 3D drawings as well as metadata for their description.
AutoDesk changes this format from version to version of AutoCAD, so older versions can only handle the files to a limited extent. DWG is a proprietary and closed format that AutoDesk constantly seeks to protect.
With the help of the free AutoDesk DWG Viewer you can convert a DWG file into another version. This is useful because many programs can import DWG files but do not always support the latest version.
DWG is the quasi-standard for CAD (Computer Aided Design) files and is also used by IntelliCAD, PowerCAD, and other programs as the default format. The free Blender software can also read DWG files using Stani's Pythonscript Architects.
AutoDesk also provides a licensed library so that many programs can read the format. However, these z.T. Limitations.
As an alternative, dxf, IGES or STEP, either directly stored or converted there, are recommended as these formats are open and therefore better supported. However, the export or conversion may be subject to restrictions.