In this paper we describe a general purpose relational data base system from both user's and system's viewpoints. The system is currently being implemented for the microprogrammable computer Interdata 85 at the Department of Computer Science, University of Kansas. The long range goal of this research is to implement a distributed data base system in a computer link where the Interdata 85 is connected to a large computer of different architecture and language capability, the Honeywell 635. Toward this goal, we propose a new physical storage structure called a binary search tree complex or BST complex. Primitives to manipulate BST complexes can be easily implemented for both machines. Queries, data manipulation operations and data definition operations specified by users can be mapped into these BST complex primitives; therefore the translation process can be independent of machine hardware. In this paper, we outline the capability of a user data language UDL-1 and its implementation in terms of BST complexes. A detailed description of all BST complex primitives appears in [LTD].