How do you xxplain the significance of Input -Process -Output cycle?

The Input - Process - Output cycle is the most basic explanation of how users interact with a computer. The Input step is where the user requests something from the computer using an input device, like a keyboard or a mouse. The Process step is when the computer takes the information and processes it internally and the final Output step is when the computer respond to the request it has processed to an output device like a monitor or a printer. This is significant because it is same way that people interact in real life. A real life example would be someone buying something from a shop. This Input step would be handing the shopkeeper money and requesting goods. The Process step would be the shopkeeper putting the money in the till and getting the good whilst the Output step would be the shopkeeper handing over the goods and the change.