Computer
Firstly, I am going to enlighten you more on what a computer is, what it does before we can move over to its mode of operation.
What is a computer
A computer is an electronic machine with the capability to accept instructions via computer programming to carry out sequence of instructions (logical or arithmetic) and finally give an output relative to the input given to it. There goes the saying for a computer "Garbage in, Garbage out".
A computer can only do what is asked of it, in the manner it is asked of it, so the computer should be seen as a machine that can always give a feedback (output) in respect to the input (data).
