BRL-CAD is an open-source, cross-platform solid modeling system that provides a suite of tools for computer-aided design (CAD). It is widely used in engineering and graphics research, and development. Known for its high-performance geometric representation and analysis capabilities, BRL-CAD includes features such as interactive 3D modeling, ray-tracing support for rendering and geometric analysis, network distributed framebuffer support, image and signal-processing tools, and libraries for robust geometric representation. This system, actively used and developed for decades, is ideal for tasks involving complex geometry and large-scale simulations.