There are many volcanoes throughout the world that are erupting today. They are mainly found in zones where plates interact called plate boundary. However, there are some volcanoes like the Hawaiian volcanoes that are not along a plate boundaries.

There is an active area that is called the "Ring of Fire" in the Pacific. In the picture it shows a large zone of where you can find active and dormant volcanoes. These are areas where the crust of the Earth is being "subducted" or destroyed under continental rock. This causes volcanism.

There are also other areas of intense volcanism under the Atlantic Ocean. This is referred to as the Mid-Atlantic Rift, and is an area that is being rifted apart. Two plates are moving in opposite direction, and the Earth "heals" the wound by the lava of the volcanoes.