The term "energy sources" refers to various methods or technologies used to generate energy, which can be harnessed and utilized for different purposes. These include traditional forms such as fossil fuels like coal, oil, and natural gas, as well as renewable resources like solar power, wind power, hydroelectricity, geothermal energy, and biomass. The term is broadly used to describe the diverse range of methods that can be employed to produce electricity or provide mechanical force, including nuclear fission and fusion.