The volcanic eruptions of volcanoes may be classified in ways based on their activity, their violence, or their relationships.

Extinct, active, and dormant categories divide into a familiar classification, and that is very important to the near-volcano people.  Easily recognized volcanoes are active volcanoes, but dormant and extinct volcanoes are difficult and dangerous sometimes.  The people living near known extinct and dormant volcanoes must always be on the lookout.  Volcanoes can erupt at any time without warnings.

The constantly erupting volcanoes are active.  The eruption is usually quiet but can sometimes be violent.  Stromboli, which lies on an island near Italy, is a famous active volcano. 

 Intermittent volcanoes erupt at fairly regular time periods.  Mount Asama, Mount Etna, and Hualalai are some intermittent volcanoes.

Inactive volcanoes that have not erupted for an amount of time but can’t be called extinct are dormant volcanoes. They can be called “sleeping” volcanoes.