- Volcanoes are openings in the Earth's surface that allow hot material from inside the planet to escape. When this material escapes it causes an eruption.
- There are around 1,500 active volcanoes in the world, most located near coastlines of the Pacific Ocean. The largest volcano on Earth is Mauna Loa in Hawaii.
- Volcanoes can be classified as active, dormant, or extinct based on recent eruption activity. Active volcanoes have erupted within the last 10,000 years while dormant and extinct volcanoes are considered inactive.