Template:POTD/2009-03-19
An illustration from U.S. Patent #223898 for the incandescent light bulb, issued to Thomas Edison on January 27, 1880. Edison's 1879 effort was the first commercially practical light bulb, coming 75 years after the incandescent lamp was invented by Sir Humphry Davy. Twenty-two other people also invented versions of the light bulb, but Edison's version was able to outstrip the others because of a combination of three factors: an effective incandescent material, a higher vacuum than others were able to achieve and a high resistance lamp that made power distribution from a centralized source economically viable.Image credit: Thomas Edison