Tagging is the process of assigning descriptive labels, keywords, or metadata to digital or physical data objects. As a research concept and methodological approach, it investigates the theories, systems, and practices associated with creating, managing, analyzing, and utilizing these annotations for purposes such as information organization, retrieval, classification, and enhanced data navigability. Its significance lies in facilitating efficient access to and understanding of large datasets, enabling personalized content filtering, and supporting collaborative knowledge construction across diverse fields.