Abstract
Descriptors are quantitative or qualitative measures that capture key properties of a system. In catalysis, they are essential for understanding the relationship between a material's structure and its function, facilitating the design and optimization of new catalytic materials and processes. Since the introduction of energy descriptors in the 1970s, various approaches, ranging from electronic properties to data-driven techniques, have been developed to construct these descriptors. This review first categorizes the different types of descriptors, including energy, electronic, and data-driven approaches. It then explores their applications in active site design and finally concludes with a discussion on the challenges and opportunities in advancing catalytic site design.