Volcano is a mountain that lava comes out from a magma chamber under the ground. Volcanoes are formed by the gesture of tectonic plates. The Earth’s Crust has broken into 17 rigid tectonic plates. Volcanoes are often found where tectonic plates are coming together or moving apart. When there is enough pressure the volcano erupts. Some of the volcanic eruptions blow out from the top of the volcano. When a volcano is active, the volcanic materials come out of it. The materials are lava, steam, gaseous sulfur compounds, ash and broken rock pieces. Volcanoes are found on planets more than earth. Volcanoes which are away from plate boundaries are caused by mantle plumes. These are called as hotspots. Volcanologists are the scientists who study volcanoes using methods from geology , chemist, geography, mineralogy, sociology and physics.. The world’s biggest volcano is named as Mauna Loa in Hawaii. Mauna Loa was created by the movement of Pacific tectonic plate which moved over the Haw