It's not entirely accurate to say that a light bulb is made of metal. While some parts of a traditional incandescent bulb are metal, the light-emitting element is a filament made of tungsten.

Here's why:

* Tungsten has a very high melting point: This is crucial for incandescent bulbs, as the filament needs to get extremely hot to emit light. Tungsten's high melting point allows it to withstand the intense heat without melting.

* Tungsten has a high resistance: This means that when electricity flows through the filament, it encounters a lot of resistance. This resistance converts electrical energy into heat and light.

* Other metal components: The bulb itself is typically made of glass, and there are metal parts such as the base, the contacts, and the support wires that hold the filament in place.

However, modern LED bulbs are different. They don't have a filament. Instead, they use light-emitting diodes (LEDs) made of semiconductor materials like gallium nitride (GaN) or gallium arsenide (GaAs). These materials emit light when an electric current flows through them.

So, while metal plays a role in both traditional and modern bulbs, the light-emitting element itself is not always metal.