People use tools from the beginning of their existence.In the past, the only power available was the muscle power augmented by primitive tools such as wedge or lever.The invention of wheel(about 300 B.C.) allowed construction of watermill and windmill(12.cent.).James Watt developed the first steam engine.It allowed sudden development of machinery and manufacturing.This period in 18th century is called Industrial Revolution.The steam engine was originally developed for draining mines but was rapidly put to use in factories and railways.Hand-made products were replaced by machine-made products.Michael Faraday invented the first dynamo(1831) and formed the basis of electrical engineering.Electricity was available from 19th century.First carbon arc lamp was invented by František Křižík and first bulb by T.A.Edison.Electricity is generated in power stations and easily flows through wires.The internal-combustion engine was ivented by German Nicholas Otto.Then two Germans, Gottlieb Daimler and Karl Benz created the first petrol-driven motocar(1885).This invention made transport faster and comfortable.Today, main sources of energy are natural gas, water power, oil, coal and nuclear power.Scientists try to use alternative sources of energy such as solar, water, wind, geothermal and tidal energy.
In the past, main materials used by humans were:wood, bone, horn, shell, stone and later bronze.The invention of the blast furnace(15th century) allowed to make cast iron.But it was expensive until the charcoal was substitued by coke(1709).This change of cheap iron started the Industrial Revolution.Soon new materials were invented such as rubber, glass, leather, paper, bricks, porcelain and later synthetic materials, plastics and drugs.This process still continues with genetic engineering(for example synthetic insulin and hormones). The main inventions which changed human life are:aircraft, radio, television, telephone, X-ray machines, radar, air-cushion vehicles(hovercraft), electric welding, photographs, birth-control methods, test-tube babies, penicillin and vitamin C.
Special application of modern technology and science are space flights.The first satellites was launched by Russians(1957) and the first human in space was Russian Yuri Gagarin in the spacecraft Vostok 1(1961).The first people who step onto the Moon were Neil Armstrong and Edwin Aldrin with spacecraft Apollo 11 (1969). At present artificial satellites are used
or scientic purposes, communications, weather forecasting and military purposes.
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