Nuclear Plants are much like fossil-fueled power plants. The idea of fossil fueled power plant is to heat up the water until it boils and changes to steam, then the steam will turn the turbine generator to produce electricity. The difference between them is the source of heat. Inside of a nuclear power plants, the heat to make the steam is created when uranium atoms split, also known as the fission.

Fission is a process that the nuclear reactor to provide heat. It is a process that a neutron, in this case uranium neutron, collides with a target nucleus, in this case is uranium nucleus. After the first collide the products are more neutron and more nucleus then the neutron will keep repeating the collision with other nucleus. The process will create heat and we use the heat to boil water.

Learned from website MIT Nuclear Reactor Laboratory