Most of us know a volcano as a landform that looks a lot like a mountain. However, unlike mountains, volcanoes have an opening that connects like a tunnel down into the Earth! It’s through this opening that a volcano will sometimes erupt.
The opening that makes up a volcano connects down into the Earth to a special layer of our planet where temperatures are really hot – so hot, in fact, that the rocks it’s made up of are melted by the heat to form a thick, liquid-like substance known as magma. A volcanic eruption usually occurs because magma and gases from inside the Earth build up and create pressure. When a volcano erupts, it can release rocks, ash, gases, and lava (erupted magma). Some eruptions are more powerful than others – while sometimes they are very explosive, other times the lava oozes out slowly.
A volcano can be dangerous for any people, buildings, or land that are in the path of an eruption. Luckily, there are usually enough warnings prior to an eruption that people can evacuate ahead of time. Additionally, volcanoes don’t necessarily erupt very often – many of them aren’t “active,” so it’s kind of like they’re sleeping!