The invention of the lightbulb was a cumulative effort involving multiple inventors over several decades, rather than the work of a single individual.

• Early developments : Humphry Davy invented the first electric light in 1802 by creating an electric arc lamp using a battery and carbon electrodes. However, it was too bright and impractical for everyday use

. Other early contributors include James Bowman Lindsay (1835), Warren de la Rue (1840), and Marcellin Jobard (1838), who developed early incandescent lamps with various filaments and vacuum tubes

• Joseph Swan : In the 1870s, English chemist Joseph Swan developed a working incandescent lightbulb using carbonized paper filaments inside a vacuum bulb. He patented his design in the UK in 1878 and demonstrated it in 1879. Swan's bulbs were among the first to be commercially viable in England, although early vacuum technology limited their lifespan

• Thomas Edison : Edison is often credited with inventing the lightbulb because he created the first commercially practical incandescent lamp in 1879. He improved on previous designs by using a high-resistance thin carbon filament and better vacuum pumps, making the bulb last longer and suitable for widespread electrical distribution. Edison and Swan eventually joined forces, forming Edison-Swan United to manufacture lightbulbs

In summary, while Thomas Edison is popularly known as the inventor of the lightbulb due to his practical and commercial success, the invention was built on prior work by many inventors, especially Joseph Swan and earlier pioneers like Humphry Davy. The lightbulb's invention is best seen as a collaborative progression rather than the achievement of a single person