SketchUp (formerly Google Sketchup) is a 3D modeling software. Developed by Trimble
License: Freemium
BRL-CAD is a constructive solid geometry (CSG) solid modeling computer-aided design (CAD) system. It includes an interactive geometry editor, ray tracing support for graphics rendering and geometric analysis, computer network distributed framebuffer support, scripting, image-processing and signal-processing tools. Developed by U.S. Army Research Laboratory
License: Open Source
Brl-CAD is a powerful open-source CAD tool best suited for engineering and scientific applications, featuring advanced geometric modeling and simulation capabilities. In contrast, Sketchup offers a more user-friendly interface ideal for architectural design and visualization, with strong collaboration tools but lacks the depth and customization of a traditional CAD software.