What is the X in X-mas?
1. State, Operator And Result. A general problem-solving production system architecture, intended as a model of human intelligence. Developed by A. Newell in the early 1980s. SOAR was originally implemented in Lisp and OPS5 and is currently implemented in Common Lisp. Version: Soar6.
["The SOAR Papers", P.S. Rosenbloom et al eds, MIT Press 1993].
2. Smalltalk On A RISC. A RISC microprocessor designed by David Patterson's at Berekeley.