A volcano has many parts. Under the volcano is a compartment of molten rock known as the magma chamber. This molten rock or magma travels from the magma chamber up through the crust of the Earth through a crack known as a vent. Hot lava exits the volcano at the crater, becoming magma. If the eruption is violent, then ash, rock and lava are launched into the air, collecting on the sides of the volcano. After many eruptions the layers of ash, rock and solidified lava build up to form the recognizable cone shape of a volcano. On the top of the cone is the crater or indentation in the volcano that marks where past eruptions have occurred.
