Nuclear fission powers are essentially the energy sources that are created through splitting atoms in order to release a large amount of energy. Although commonly referred to as nuclear fission, there are alternative phrases that can be used to describe this type of process and the energy it generates. One term that can be used is atomic power. This refers to the energy that is harnessed through nuclear reactions and is often used in power plants. Another phrase that can be used is nuclear energy. This encompasses any energy source that is generated through nuclear reactions including nuclear fusion, which is the opposite of nuclear fission. Ultimately, whether it is referred to as nuclear fission, atomic power or nuclear energy, the process remains the same, splitting atoms to generate energy.