How is Metadata different from a Data dictionary?

Metadata describes data. It has information about how and when, by whom certain data was collected, and the data format. This data of data or metadata is essential to understand information that is stored in data warehouses and XML-based web applications.

On the other hand, A data dictionary contains the basic definitions of a database. There is a list of files in the database, the number of records in each file, and information about the fields in the data dictionary.