SketchUp is an easy-to-learn 3D modeling program that enables you to explore the world in 3D. With just a few simple tools, you can create 3D models of houses, sheds, decks, home additions, woodworking projects - even space ships.
Note: SketchUp is free for personal use. Pro version can be found here.
Added support for macOS Catalina, which included the following updates: