3.1 Information: A Fundamental Quantity The trail-blazing discoveries about the nature of energy in the 19th century caused the first technological revolution, when manual labor was replaced on a large scale by technological appliances—machines which could convert energy. In the same way, knowledge concerning the nature of information in our time initiated the second technological revolution where mental “labor” is saved through the use of technological appliances—namely, data processing machines. The concept “information” is not only of prime importance for informatics theories and communication techniques, but it is a fundamental quantity in such wide-ranging sciences as cybernetics, linguistics, biology,...