When people think of the light bulb, they just think of Edison. That is not the case.
in 1802, Humphry Davy created the first electric light. He heated carbon with a battery until it started to glow. This was known as the electric arc lamp. This invention didn't work because it didn't last very long and was just too bright for an practical uses.
In 1840, Warren de la Rue enclosed a coiled platinum filament in a vacuum tube and passed an electric current through it. The design was based on the fact that the height melting point of platinum would allow it to operate at high temperatures and that the evacuated chamber would contain fewer gas molecules to react with the platinum. Although this was an efficient design, the high cost of platinum prevented it's use in the commercial market.
In 1850, Joseph Wilson Swan enclosed carbonized paper filaments in an evacuated glass bulb, but the lack of a good vacuum and adequate supply of electricity resulted in an ineffective producer of light.
There were many variations of a light emitting device before Edison, but he was the first to make a commercially viable model. Since there have been many different models, and there will continue to be changes in the future.