How are they are formed!
Volcanoes are formed when plates push together then one slides under the other. Magma rises like vapor then BOOM it erupts. Lava can flow fast or slow. Some volcanoes don't use lava they use ash and rocks.
Hawaii has black beaches the sand is so hot you can't step on it without shoes. This was caused by a volcano.
See how the smoke is rolling down Ontake.
Lightning is striking the magma.
Under water volcano
The volcano is under water and its erupting.