Kinds of volcanoes . The life of a volcano Volcanic eruptions Activities Other Internet Resources About Volcanoes . Volcanoes are places on the Earth s surface where hot lava from deep in the Earth is erupted, or brought up to the surface. Volcanoes are usually recognized by their conical shape, with a crater in the middle.
Some volcanic cones have steep sides, and some have gentle sides.
The sides of the volcano are made up of layers of lava and ash that have erupted from the volcano. Lava comes out of volcanoes mainly through the top, known as a vent. After the eruption has finished, the vent usually collapses, and is left behind as a crater. The crater is often called a caldera. The vent is a long pipe that goes down into the earth deep beneath the volcano, and taps the pool of hot molten magma lying beneath the volcano.