EVA principle
The EVA principle reflects the basic structure of a computer. "E" stands for input, "V" for processing and "A" for output.
Looking at the individual components, the range of peripheral devices for data input extends from keyboards to mice, joysticks, light pens and touchscreens to scanners, graphics tablets, digital cameras and camcorders. In addition, there are readers for the various card formats and for biometricdata.
The centralprocessingunit with its arithmetic logic unit, control unit and main memory is responsible for data processing, and a comprehensive range of monitors, printers, plotters,imagesetters and multimedia output devices is available for data output.
In addition to the components mentioned in the EVA principle, modern computer architectures have extended storage capabilities and communication facilities.