BRL-CAD is a computer aided design system. It was originally created in 1979 at the U.S. Army Ballistic Research Laboratory to perform simulation and analysis of "combat vehicle systems and environments." It retains an emphasis on engineering analysis but has grown to become a general purpose system for both Computer Aided Design (CAD) and 3D modeling workflows. BRL-CAD follows the UNIX design philosophy of providing small, composable tools that can be combined as the user sees fit to support their workflow. Rather than providing a single monolithic application that seeks to solve every problem, BRL-CAD offers a set of purpose-built tools that exchange data in a set of common file formats. In the Gallery section of the BRL-CAD site users can locate examples created with the software. The Docs section includes both detailed reference materials and a variety of tutorials. The Download section of the site offers installers for Windows, macOS, Linux, and a variety of UNIX systems.