Abstract: In systems, such as graphic screens where activation of functions takes place by means of initiation signals, a certain period of time normally elapses from the initiation signal to the implementation of the given function. By providing an indication of the span of time from the moment when the initiation signal is applied and until it actually activates the function, a user-friendly function activation can be established in an easy and clear manner, the user having constant control of the amount of time left until the function is activated. Additionally, the user may either provide a regret signal in the time between the function activation and the initiation signal, or provide an accelerated function activation. This time is variable, so that it can be adapted to various users, such as handicapped, experienced or unexpedienced users. The indicator is usually designed as a graphic picture, e.g.