Femtochemistry is a branch of chemistry that studies chemical reactions on extremely short timescales, typically in the range of femtoseconds (one quadrillionth of a second). This field emerged in the 1990s, allowing scientists to observe the movements of atoms and molecules during chemical reactions, providing insights into how these processes occur at a fundamental level. By using advanced laser techniques, researchers can create and measure ultrafast light pulses that capture the dynamics of molecular interactions. This has significant implications for understanding photosynthesis, enzyme function, and the development of new materials, ultimately enhancing our knowledge of chemical processes in nature and technology.