Adenosine triphosphate (ATP) is the indispensable energy currency of the cell, essential for powering nearly all biological processes. Structurally, ATP comprises an adenine base attached to a ribose sugar, linked to three phosphate groups, with energy stored in the high-energy bonds between these phosphates. During hydrolysis, ATP releases energy by breaking the terminal phosphate bond, transforming into adenosine diphosphate (ADP) or adenosine monophosphate (AMP), and driving a wide array of cellular functions including muscle contraction, active transport across cell membranes, and biosynthetic reactions. The regeneration of ATP is a continuous process facilitated by cellular respiration mechanisms like glycolysis, the citric acid cycle, and oxidative phosphorylation within mitochondria, underscoring its pivotal role in sustaining cellular metabolism and homeostasis. Moreover, ATP is not only a fuel source but also plays a critical role in cell signaling and regulation, acting as a substrate for kinases in phosphorylation reactions and as a signaling molecule in its own right. Thus, ATP’s multifaceted roles highlight its fundamental importance in both energy transfer and regulation within living organisms.