What part of a light bulb acts as a resistor which gets hot and gives off light?

The part of a light bulb that acts as a resistor and generates heat to produce light is the filament. Typically made of tungsten, the filament heats up as electric current passes through it, reaching a high temperature that causes it to emit light through incandescence. In modern LED bulbs, the light-emitting diodes (LEDs) serve a similar purpose, though they operate through different principles.