Autodesk Inventor supports IDW and DWG file types for drawings. Both file types produce identical drawings. IDW files are the native Inventor format. You can open them only in Inventor or Inventor View. This file type results in smaller file sizes.
The DWG file type is native to AutoCAD®. You can open DWG files in AutoCAD, Inventor, or DWG TrueView. If you create data using Inventor in a DWG file, you can modify the data only with Inventor. If you create data using AutoCAD in a DWG file, you can modify the data only with AutoCAD. If a downstream consumer of your Inventor data needs a DWG file, consider using DWG files as the default in Inventor.