Std Open

Opens and loads project files into FreeCAD's workspace and depending on the installed extension modules further file types are supported such as *.IGES, *.STEP, *.BREP, *.STL, *.OBJ, *.PLY, etc.

When loading files always a new document gets created. If you want to load a file into an existing document use the Std_Import instead.

FreeCAD project files have the extension "FCStd". To get more information about the internal layout of FreeCAD projects files read the article File Format FCStd.