Negative feedback

Negative feedback is a basic concept of cybernetics; it is the basis of regulation and control. It is important in engineering and physiology. In biology and physiology negative feedback is known as homeostasis.^[1]

Negative feedback occurs when the output of a system acts to oppose changes to the input of a system. This has the result that the changes are made less, and the system kept within limits. The classic example is a central heating system which cuts off when a (suitably placed) temperature sensor hits a pre-set mark. The negative feedback part is the thermostat.

1. ↑ Raven P.H. & Johnson G.B. 1999. Biology. 5th ed, Boston: Hill. p1058