Cytidine is a nucleoside composed of cytosine and ribose, integral to the synthesis of RNA and DNA, where it serves as a fundamental building block for these genetic materials. This compound plays a critical role in the storage and transfer of genetic information within cells, contributing to the formation of nucleic acids crucial for cellular functions. Beyond its role in nucleic acid synthesis, cytidine is involved in various metabolic pathways and regulatory processes within the body, influencing protein synthesis, energy metabolism, and gene expression. Its presence is essential for maintaining cellular integrity and supporting the physiological processes necessary for life and function across biological systems.