System/K: A Knowledge Base Management System

System/K is a Knowledge Base Management System designed to offer a set of facilities for knowledge representation and usage at the conceptual level by means of three descriptive mechanisms ("Aggregate", "derive", and "Collect"). Two specific object-types (Assertions and Sets) are defined to represent the "part-of", "is-a" and "member-of" relationships. An "object-Oriented" cross-reference logic is defined, that saves users from having to be constantly aware of "keys". System/K refers to SQL/DS (a relational DBMS) to maintain information concerning both the conceptual relationships (meta-database) and the description of the entities in the real world (database).A logic is defined to generate the appropriate relation schemes starting from the conceptual definitions.