Outlines a general view of information systems supporting a company's operations and management. Emphasize that management support systems (MRS), decision support systems (DSS), and executive information systems (EIS), rest on the foundation of transaction processing systems (TPS) that support business operations. TPSs are the major source of data used by the higher-level systems to derive information. Professional support systems (PSS) and office information systems (OIS), which support individual and group knowledge work, are also a part of this foundation