A volcano is a geologic formation from which molten rocks (lava) and hot gases emerge onto the surface of the planet. Typically a volcano is a mountain from which molten material is emitted. It can also be a simple fissure in Earth's surface, which will over time develop as a mound or mountain (after lava cools down and deposits). A volcano is connected to the magma chamber under the surface of Earth. This chamber has molten rocks which flow out from the volcano. The actual outflow of the lava takes place from one or more openings, known as the vents. There is usually a primary vent and many smaller vents. Lava emerges from the vents and flows outwards. Over time it cools down and deposits, forming other parts of the volcano.
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