pon gen- erations of microprocessor technologies on that same platform, whereas Microsoft and other software companies followed by developing more sophisticated operating systems and applications. An entire software industry was created, changing the method of computing. THE CLIENT-SERVER MODEL Huge armies of PCs in large corporations and organizations were soon connected to LANs, access- ing information on larger machines. These included departmental machines and more traditional mainframes. The idea had originated at IBM in the early 1980s and was dubbed cooperative computing. IBM wanted to put a network of industrial PCs in charge of programmable logic controllers (PLCs) on small manufacturing area LANs. The PC would control and feed the controllers with production data running on older Series/1 systems. These systems would in turn receive production planning and con- trol information from mainframes mostly through traditional synchronous links such as SDLC/BSC protocols over coax connections supporting 3270 terminal emulation software and SO on. Connectivity between different computer systems became critical. For example, bridges allowed the interface between UnibusTM systems from DEC and IBM channels or between IEEE 802.4 Manufacturing Automation Protocol (MAP) industrial buses. At the time, MAP industrial buses were favored on the shop floor by the automotive manufacturing world, and Ethernet LANs were favored in the engineering realm, where VAXs and Apollo workstations lived and worked together. The idea was simple: The individual PC (the client) would run applications locally, but whenever data was needed, it would have to be fetched from a server computer transparently to the user. The server would usually be a much more powerful machine that was situated upstream on the network hierarchy where databases were being kept around the clock. This model would ultimately require a radical rethinking of the programming methodology. New tools had to be developed, from program- ming languages all the way to the a