2.1. Input devices;
Input is the term denoting either an entrance or changes which are inserted into a system and which activate/modify a process. It is an abstract concept, used in the modeling, system(s) design and system(s) exploitation. It is usually connected with other terms, e.g., input field, input variable, input parameter, input value, input signal, input device and input file.
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2.2. Storage devices;
To help keep files saved and not lost.

2.4. Output devices.
Output is the process of transmitting information or the transmitted information itself. Essentially, output is any data exiting a computer system. This could be in the form of printed paper, audio, video. In the medical industry this might include CT scans or x-rays. Typically in computing, data is entered through various forms (input) into a computer, the data is often manipulated, and then information is presented to a human (output).
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