From the beginning of people's existence they have used tools, various types of energy and materials, generally for the purposes of production of nearly everything in our world. Almost every human process s for getting food and shelter depends on complex technological systems. At present, modem industry largely depends on power, materials, machinery and production processes. In early human history, the only power available was muscle power augmented by primitive tools, such as the wedge or lever. The invention of the wheel (about 300 B.C.) was followed by the watermill and windmill (12th cent. A.D.). Not until the 18th century did an alterative source of power appear in the form of the first working steam engine developed and improved by James Watt. The steam engine and other technical advances made possible the replacement of traditional agrarian economy by one dominated by machinery and manufacturing. The sudden acceleration of technical and economic development that began in Britain in the second half of the 18th century is called the Industrial Revolution. This transferred the balance of political power from the landowner to the industrial capitalist and created an urban working class. The steam engine was originally developed for draining mines but was rapidly put to use in factories and on the railways. Hand-made products were replaced by machine-made products which increased in number, and together with faster transportation by means of a railway, this meant a significant change in industry. Michael Faraday's demonstration of the dynamo in 1831 revealed the potential of the electrical motor and became the basis of electrical engineering. Electricity generated on a commercial scale was available from the early 1880s and was used for electric Qlotors which powered all kinds of machinery and for lighting, first by carbon arc lamp, invented by František Křižík 1880, and byan electric bulb invented by Thomas A. Edison in 1879. Electricity is the most useful and most convenient form of energy, readily convertible into heat and light and used to power machines. Electricity can be generated in one place (power stations/plants) and distributed anywhere because it readily flows through wires. The invention of the internal-combustion engine by German scientist Nicholas Otto in 1876 enabled two Germans, Gottlieb Daimler and Karl Benz to create the first petrol-driven motorcar (1885).