A ZW1 file is a compressed file format used by some CAD software, including ZWCAD and other compatible applications. It contains 2D or 3D design data, similar to DWG files. Wwwxxxsco
A DWG (AutoCAD) file is a proprietary file format used by Autodesk's AutoCAD software for storing 2D and 3D design data. --- Microelectronic Circuits Sedra Smith 8th Edition Pdf