The filament is enclosed in a glass bulb with a vacuum or inert gas to protect the filament from oxidation. Current is supplied to the filament by terminals or wires embedded in the glass. A bulb socket provides mechanical support and electrical connections.
Incandescent bulbs are manufactured in a wide range of sizes, light output, and voltage ratings, from 1.5 volts to about 300 volts. They require no external regulating equipment, have low manufacturing costs, and work equally well on either alternating current or direct current. As a result, the incandescent bulb became widely used in household and commercial lighting, for portable lighting such as table lamps, car headlamps, and flashlights, and for decorative and advertising lighting.
In 1802, Sir Humphry Davy, an English physician, created the first electric light by passing a current through a platinum strip. The glow did not last long, but it marked the beginning of the history of light bulbs. In 1875, Pavel Nikolayevich Yablochkov, a Russian electrical engineer and inventor, developed the first practical arc lamp known as the "Yablochkov Candle." Yablochkov used two parallel carbon rods to extend the life of the battery. During the late 1880s, Thomas A. Edison and many other inventors began to experiment with incandescent lamps in search for a reliable and economical form of indoor lighting.
One of the biggest changes was to the working industry. Before, work had been limited to the day for most. Factories and shops would close once dark fell, which of course changed throughout the year, but now, they could continue to work under the bright light of the bulbs 24 hours a day. It revolutionised how we view work and paved the way for a century of very fast progression.