There are three main types of volcanoes: composite volcanoes, cinder cone volcanoes, and shield volcanoes. Composite volcanoes are tall and explosive, producing lava flows, ash, and cinders. Cinder cone volcanoes are simple and bowl-shaped, characterized by cinders but no ash. Shield volcanoes are broad, flat, and round with craters and vents. Most volcanoes are located around the Pacific Ring of Fire.