VariCAD Viewer BRL‑CAD gCAD3D STP Viewer Let’s talk about these STP file viewer software in detail! FreeCAD FreeCAD is a free and open-source CAD design software that allows you to view STP files.

How to Open DWG Files in Illustrator. The DWG format was originally designed by Mike Riddle in 1977 and licensed to AutoDesk Inc. in 1982 for creating two- and three-dimensional drawings.