How Does A "Light Bulb" Light?

The incandescent light bulb, commonly called as simply a light bulb, is a basically a source of artificial light which functions by the process of incandescence.

An incandescent bulb is mainly comprised of an enclosure made out of glass (the bulb), an inert gas and a tungsten filament. Here's the basic process of its functioning:

An electric current is passed through the tungsten filament in the bulb which causes it to heat up and release thermally equilibrated photons, hence resulting in continuous light. The glass enclosure stops the oxygen from entering and coming in contact with the hot filament, which otherwise who have been quickly shattered due to oxidation.

The filament gets heated to a pretty high temperature, usually at around 2000 to 3300K, depending on what kind of filament is used.