Feedback

It is sometimes good to have feedback in an ICT system. This is when the outputoutput: the term denoting either an exit or changes which exit a system and which activate/modify a process from a system feeds back to influence the inputinput: the term denoting either an entrance or changes which are inserted into a system and which activate/modify a process and the process repeats itself.

A good example is a system set-up to control water temperature in a tropical fish tank. The temperature of the water is taken as an input from sensorssensor: an automatic input device that continuously monitors a set of computer controlled parameters, eg a parking sensor detects how close a vehicle is to the nearest object and alerts the driver if the distance falls outside of the specified parameters. Processing takes place and the temperature of the water is compared against the pre-programmed parameters, eg maximum/minimum temperature. The outputs include the automatic decision to either turn on or off the heater to warm or let the water cool. The output, ie the change in the water's temperature, is then fed back by the sensors as an input and the process repeats itself.

A system that monitors the water temperature of a fishtank and reacts accordingly.

Feedback can occur in informationinformation: data with context or meaning-based systems as well. Often an output will have a result on further inputs. For example, the output of accepting an online booking for an air ticket will be to reduce the number of tickets available.

The Measurement and control section has more information about the feedback cycle.