perpetual motion machine
hypothetical device capable of producing (mechanical) energy from nothing, alternatively from surrounding heat
magic wheel
perpetual motion machine reportely built in 8th-century in Bavaria, Europe
perpetual motion machine of the first kind
hypothetical machine that produces work without any incoming energy at all, violating the first law of thermodynamics: the law of conservation of energy
perpetual motion machine of the second kind
hypothetical machine that produces work using heat from the surroundings (at low temperature) as source of energy, violating the second law of thermodynamics