Nuclear fuel is a material used in nuclear reactors to produce energy through a process called nuclear fission. The most common types of nuclear fuel are uranium and plutonium, which can release a large amount of energy when their atomic nuclei are split. This energy is harnessed to generate electricity in power plants. Before use, nuclear fuel is often processed into small pellets and assembled into fuel rods. These rods are placed in the reactor core, where they undergo fission reactions. The heat generated from these reactions is then used to produce steam, which drives turbines to generate electricity.