After the Dane Hans Christian Ørsted demonstrated that it was possible to deflect a magnetic needle by closing or opening an electric circuit nearby, a deluge of papers attempting explain the phenomenon was published. Michael Faraday set himself to the task of clarifying the nature of electricity and magnetism by experiments. In doing so, he devised what could be described as the first electric motor (though it does not resemble a modern one), a transformer (now used to step up the voltage and step down the current or vice versa), and a dynamo (which contains the basics of all electric turbine generators). The practical value of Faraday's research on electricity and magnetism was nothing short of revolutionary. A dynamo converts mechanical energy into an electrical current whilst a motor does the reverse. The world's first power plants entered service in 1883, and by the following year, people realized the possibility of using electricity to power a variety of household appliances. Inventors and engineers soon raced to develop such items, starting with affordable and durable incandescent light bulbs, perhaps the most important of the early applications of electricity.