Strawberry Prolog This Prolog compiler for Windows 95/98/NT and Unix/Linux supports OLE and Prolog CGI Scripts. Strawberry Prolog is suitable for client-server applications and has unique debugging facilities.
Trinc-Prolog, an object oriented prolog for Windows Trinc-Prolog is a new development tool for the prolog language. Trinc-Prolog supports the ISO Prolog standard and has extended the prolog language with innovative object oriented features. TPWIN,an OO class library is available to develop Windows applications.
Visual Prolog A full-featured programming environment is offered with all the facilities necessary to write mission-critical, commercial-grade applications. A freeware version is available.
The YAP Prolog System The University of Porto's Edinburgh-style, WAM-based Prolog engine is available on 32-bit machines running Sun and Linux and 64-bit Alphas running OSF UNIX and Linux. An open-source policy is being implemented with regard to distribution.