Nuclear weapons are explosive devices, bombs, or warheads that release nuclear energy. Their destructive power comes from the core of the atom, the nucleus. One type of nuclear weapon, the atom bomb, and uses the energy released when nuclei of heavy elements like uranium or plutonium, split apart. A second even more powerful type of nuclear weapon, the hydrogen bomb, and uses the energy released when nuclei of light elements, types of hydrogen atoms, are forced together, or fused. Nuclear devices have been fashioned into weapons of many shapes with many purposes. Nuclear bombs can be dropped from airplanes; missiles launched from land, air, or sea can deliver warheads; artillery shells can be fired from cannon; mines can be placed in land and sea. …