A volcano is an opening on the surface of the earth where melted rock (called magma) is ejected above the surface of the earth as lava.

volcanoes occur where tectonic plates come into contact with one another. there are approximately 1,000 active volcanoes in the world, many of them in an area known as the "Ring of Fire" which circles the Pacific Ocean.

Primary Types of Volcanoes

Types of Eruptions

Types of Ejected Materials (volcaniclastic particles)