Home > Encyclopedia of Science > Nuclear Weapons

• Fission weapons
• Words to Know
• Fusion weapons
• Effects of nuclear weapons
• Nuclear weapons today
• Radioactive Fallout
• Nuclear weapons treaties

Nuclear weapons are destructive devices that derive their power from nuclear reactions. The term weapon refers to devices such as bombs and warheads designed to deliver explosive power against an enemy. The two types of nuclear reactions used in nuclear weapons are nuclear fission and nuclear fusion. In nuclear fission, large nuclei are broken apart by neutrons, forming smaller nuclei, accompanied by the release of large amounts of energy. In nuclear fusion, small nuclei are combined with each other,...