Complex compounds are an essential class of chemical species that play a pivotal role in various scientific and industrial fields. The accurate classification and nomenclature of these compounds are critical for effective communication, research and development. This work presents a comprehensive and systematic approach to the classification and nomenclature of complex compounds, integrating the latest advancements in the field. First, we provide an in-depth overview of the fundamental concepts, structural features, and bonding characteristics of complex compounds, emphasizing their diversity and unique properties. We then propose a hierarchical classification system that encompasses major categories, including coordination complexes, organometallic compounds, and supramolecular assemblies. This system allows for a more nuanced understanding of the relationships between different classes of complex compounds and their properties. To facilitate consistent and clear communication within the scientific community, we present a standardized nomenclature framework based on the recommendations of the International Union of Pure and Applied Chemistry (IUPAC) and current best practices. This framework addresses the naming conventions for various aspects of complex compounds, such as ligands, coordination spheres, oxidation states, and geometrical isomerism. Additionally, this work highlights the significance of complex compounds in various applications, ranging from catalysis and materials science to biological systems and environmental chemistry. In conclusion, the proposed classification and nomenclature system not only fosters a better understanding of complex compounds but also serves as a foundation for future research and discovery in this rapidly evolving field.