Did Edison really invent the lightbulb?

Thomas Edison did not invent the lightbulb from scratch, and the more accurate story is more interesting. Inventors had been creating electric lights for decades before him: Humphry Davy demonstrated an electric arc light in the early 1800s, and several others, including Britain's Joseph Swan, built working incandescent bulbs in the 1860s and 1870s. What Edison and his team at Menlo Park did in 1879 was create the first incandescent bulb that was practical, one with a long-lasting carbon filament that burned for many hours, was affordable to make, and could be produced at scale, turning a laboratory curiosity into something you could actually light a home with. Swan's parallel work was close enough that the two eventually merged their British interests into a joint company rather than fight it out.

Edison's greater and often underappreciated achievement was systemic. A bulb is useless without electricity to run it, so Edison and his company built the entire infrastructure to make electric lighting viable: power generation, distribution wiring, meters, sockets, switches, and the first central power stations to deliver electricity to customers. He was inventing an industry, not just a bulb. This is why the popular Edison-invented-the-lightbulb story is both wrong and understandable: he was the one who made electric light real for ordinary people, backed by relentless experimentation (the famous thousands of failed filament tests) and formidable business and self-promotion skills. The honest framing is that Edison perfected and commercialized the incandescent bulb and built the world to power it, rather than inventing the concept, and the many earlier and contemporary inventors, Swan especially, deserve a share of the credit the popular myth erases.