What change results in release of energy?

The release of energy typically occurs during exothermic reactions, where reactants transform into products while releasing energy, often in the form of heat or light. This change can happen in various processes, such as combustion, where fuels react with oxygen, or in the formation of chemical bonds, where the energy released is greater than the energy required to break the bonds of the reactants. Additionally, nuclear reactions, such as fission and fusion, also release significant amounts of energy.