What are free tools for understand primitives 3D models?

Free tools to understand 3D primitives (basic shapes like cubes, spheres, cylinders) let you interactively create, modify, and visualize them—key options are Blender, Tinkercad, and SketchUp Free. - Blender: Advanced controls for adjusting primitives, great for deeper learning. - Tinkercad: Drag-and-drop simplicity (browser-based, no install) perfect for beginners to experiment. - SketchUp Free: Combines primitives into simple models, showing how basics build complexity. For newbies, start with Tinkercad—it’s the easiest way to grasp primitives without hassle.