My original answer was longer, but this is hopefully clearer. Small programs are often split: Input Parsing. Process. Output presentation. We can think of MVC

My original answer was longer, but this is hopefully clearer. Small programs are often split: Input Parsing. Process. Output presentation. We can think of MVC where the View is the output presentation. The Model does the processing. The Controller does the initial input parsing, determining which part of the process to pass control to. The Controller as "dispatcher" or coordinator.