SWI-Prolog Wiki entry There is a wiki entry at the SWI-Prolog Discourse Group with a lot of links. Gentle introduction A paper describing SWI-Prolog in general An Overview of the SWI-Prolog Programming Environment (January 2003) Learn Prolog Now by Patrick Blackburn, Johan Bos, and Kristina Striegnitz. Available in book form since 2006, too. In English and French (" Prolog tout de suite " ... but