The principle that claims energy cannot be created or destroyed is known as the first law of thermodynamics. This foundational concept in physics states that the total energy of an isolated system remains constant, although energy can change from one form to another (for example, from thermal energy to mechanical energy). This principle has profound implications for various scientific fields, influencing studies related to heat transfer, chemical reactions, and engineering. Understanding this law is essential for analyzing energy transformations in physical systems and processes.