Final answer:
A data dictionary is a centralized repository that provides information about the structure of data, while metadata refers to the characteristics and properties of the data.
Step-by-step explanation:
Data dictionary is a centralized repository of data that provides information about the structure, meaning, and relationships of the data. It typically includes details about data types, field lengths, and validation rules. On the other hand, metadata refers to data about data.
It provides information about the characteristics, properties, and attributes of the data, such as the source, format, size, and access permissions. For example, in a database, the metadata may include information about tables, columns, indexes, and relationships.