A nuclear bomb is a powerful weapon that releases energy through nuclear reactions, either fission or fusion. In fission bombs, heavy atomic nuclei, like those of uranium or plutonium, are split apart, releasing a massive amount of energy. Fusion bombs, also known as hydrogen bombs, combine light nuclei, such as hydrogen isotopes, to create an even larger explosion. These bombs can cause widespread destruction and loss of life due to their immense explosive power and the resulting radiation. The use of nuclear bombs has been a significant factor in global politics, particularly during the Cold War, when countries raced to develop their own nuclear arsenals.