The diagram below shows the main features of a volcano.
The magma chamber is a large underground pool of magma. Under pressure, the magma in the chamber can rise up the main vent, which is the central tube through the volcano. Volcanoes typically have a bowl-shaped basin at the top of the volcano, known as a crater. When magma reaches the surface, it is known as lava. Eruptions from other vents may lead to the formation of secondary cones on the flank (side) of the volcano.
Volcanoes can be grouped by their shape, composition (their chemical make up) and their eruption types. Find out more about the different types of volcano.