What is a data dictionary?

A data dictionary is fundamentally a manual that provides comprehensive definitions and descriptions of the data elements used within a database or data system. It serves as a reference that helps users understand the data's structure, types, constraints, and relationships. By clearly outlining what each data element represents, including its datatype, allowable values, and any associated metadata, a data dictionary facilitates effective data management, ensuring consistency and accuracy in data usage across an organization.

This clarity is crucial for maintaining data integrity and for enabling various stakeholders, such as developers, data analysts, and business users, to interpret and utilize the data correctly. Having such structured documentation is an essential practice in data governance and management.