The term electronic data processing is an obsolete term for systems that automatically process information. The systems used for this purpose require programs to execute the instructions, commands, rules and regulations. The processing of data takes place in the phases input, processing, output according to the EVA principle.
In the input phase, data is made available to the central processing unit( CPU) of a data processing system, which processes it further. In the processing phase, data are assigned to each other, compared with each other, converted or, if necessary, new data are calculated. In the output phase, data is stored or output for further processing so that it can be read again.
A data processing system can execute jobs one after the other, in which case it is batch mode, or in dialog mode. In this mode of operation, the user can communicate directly with the data processing system and actively intervene in the program sequence.