A volcano is an opening in the Earth's crust. It allows hot magma, ash and gases to escape from below the surface.
- Magma chamber - large underground pool of magma
- Lava - magma, once it reaches the surface
- Crater - bowl-shaped basin in the top of the volcano
- Vent - central tube which magma travels through
- Secondary cones - eruptions from other vents may build up secondary cones on the flanks
- Ash, steam and gas - material thrown out by the volcano
- Volcanic bombs - larger material thrown out by the force of eruption