Thomas Edison is most commonly credited with inventing the first commercially practical incandescent light bulb. However, the light bulb was developed over many years by several inventors.
Key inventors
- Humphry Davy created some of the earliest electric lights in the early 1800s, demonstrating that electricity could produce light but not yet in a practical bulb form.
- Joseph Swan in Britain developed an early incandescent lamp using carbonized filaments and received a patent in 1878, demonstrating working lamps before Edison’s commercial success.
- Thomas Edison improved filament materials and the overall lamp design, and in 1879–1880 he patented and commercialized a long‑lasting incandescent bulb that could be used widely in homes and businesses.
Short answer
When people ask “who discovered the light bulb,” the usual answer is Thomas Edison, because his 1879–1880 design was the first practical, mass‑market incandescent bulb.
Historically, though, it was a cumulative invention built on work by Davy, Swan, and others before him.