The architecture of IT systems has gone through several revolutions since early mainframe systems. Mainframe systems handled all data-management, computing, or business logic, and were housed in a very large cabinet. Early mainframes performed data processing in batches and could only be accessed by dumb terminal emulators with no intelligence, and dedicated printers. They had limited support for graphical user interfaces (GUIs) and couldn’t access multiple databases from dispersed locations.
With the introduction of the personal computer (PC), small-to-medium-sized businesses could afford to shift their business functions and data to PCs, where the processing could be controlled by the user. The Early PCs were closed systems limited to a single PC and had limited memory and data storage capabilities, and a PC...
