If you're shocked to learn that Thomas Edison didn’t invent the light bulb, you're not alone. Although we associate the great inventor's name with incandescent bulbs, Edison merely refined and expanded on his own experiments, and on decades of discoveries by other inventors and scientists. His goal was to create a practical (more efficient and longer lasting) light. He did just that.
The bulb Edison introduced with his famous 1880 U.S. Patent (No. 223898) for "an Improvement on Electric Lamps and in the method of manufacturing the same" boasted a longer lifespan (100 hours) than all previous bulbs. That patent and the fact that Edison later established methods for commercial production of incandescent bulbs, helping to make electric lighting attainable and affordable for the general public, are why he is commonly touted as the inventor of the light bulb.
However, the first person to produce light by incandescence was English chemist Sir Humphry Davy. In 1802, nearly 80 years before Edison's patent, Davy used a battery (then barely in its initial development) to pass electric current through a strand of platinum, creating light (and heat — see "Handy Fact," below). That was the start of a race to engineer an efficient and safe form of electric light – and one that would glow for more than a moment.
Throughout the 19th century, scientists in Europe and North America made important strides toward creating functional incandescent bulbs. In search of a long-burning, durable filament material, various inventors tried platinum (too costly), powdered charcoal (Frederick de Moleyns, 1841), carbon (John W. Starr, 1845), carbonized bamboo and eventually tungsten. They found that coiled filaments produced more light and that a filament's lifespan could be extended by encasing it in a vacuum tube. Even better were evacuated bulbs filled with inert gas. Many of these discoveries occurred before Thomas Edison was even born.
Edison's 1880 bulb was concurrent with the incandescent lamp patented by Britain's Sir Joseph Swan. The Swan Electric Lamp Co. began to manufacture incandescent bulbs just one year later, and Swan's house was the first one ever to be lit by electricity — with power created by a generator.
The generator may have worked for Swan’s purposes, but it highlighted another hurdle that had to be overcome: Even the most practical light bulb would be impractical (even impossible) without a functional and readily available power source and a set of standards for accessing it. Edison was key to providing solutions to both of those challenges. The screw-in bulb base, for example, was branded by his General Electric Co. in 1909 and is the most common fitting we use today.
Many early discoveries in the quest for electric light eventually sparked other lighting technologies. The 1800s’ experiments with arc or vapor lights showed that when combined in a vacuum tube, electricity and mercury (or other gases) created a chemical reaction that produced light — they fluoresced. The use of that technology (in the form of CFLs) and other developing lighting options (halogen bulbs, LEDs, etc.) reflect the ongoing drive for efficiency. I imagine that if Edison were alive today, he would be working to perfect all of them, especially the inefficient heating element we call the incandescent bulb.
HANDY FACT: Incandescence is defined as "the glowing of a body due to its high temperature." The heat that radiates from an incandescent bulb is not a side effect of light; rather, the light is a byproduct of the heat. Essentially, incandescents are heat bulbs first, then light bulbs.