In physics, the principle that states energy cannot be created or destroyed is known as the law of conservation of energy. This fundamental concept asserts that the total amount of energy in an isolated system remains constant over time. Energy may change forms, such as from kinetic to potential energy, but the total energy within the system remains unchanged. This principle underlies various physical processes and helps scientists understand energy transfer in mechanical, thermal, and chemical systems, guiding the study of conservation laws in physics.