The difference between an endothermic and exothermic reaction lies in their energy exchange with the environment. An endothermic reaction absorbs heat from its surroundings, resulting in a temperature drop in the environment and requiring energy input to occur. Common examples include photosynthesis and the melting of ice. Conversely, exothermic reactions release energy, primarily in the form of heat, which often raises the temperature of the surroundings. Combustion and respiration are typical examples of exothermic processes. Understanding this distinction is vital in fields such as thermodynamics and chemistry, where energy transformations are fundamental.