SWI-Prolog is an implementation of the Prolog language which aims to provide a free, user-friendly, fast, and scalable platform for learning Prolog, for doing research in logic programming, and for application development. With its XPCE graphics library, it provides a development environment for Prolog and portable (Unix/X11, Windows, and Mac OS X) graphics to applications. It features a very fast compiler, compliance to ISO and many de-facto standards, scalability, modules, garbage collection (even for atoms), fast two-way C and C++ interfaces, embeddability, last-call optimization, and portability (ANSI-C, 32 and 64-bit platforms).
