The primary role of ATP (adenosine triphosphate) in cells is to serve as the main energy currency. ATP stores energy in its high-energy phosphate bonds and releases it when these bonds are broken, allowing cells to perform various functions such as muscle contraction, active transport, and biochemical reactions. ATP is produced during cellular respiration, glycolysis, and photosynthesis, making it essential for sustaining life. The continuous regeneration of ATP ensures that energy is available as needed for cellular activities.