Metadata is all the information that makes data easy to find, interpret, and govern
Metadata is anything that provides context to data - additional information that helps us find, govern and use it.
Think about a book in a library. The book’s genre, description and synopsis are all its metadata. So are its physical location in the library, who has checked it out and the material it’s bound with. It’s everything to do with the book that is not the book itself, which, if interpreted broadly, means there’s a lot of metadata out there.
In the world of information management, all metadata falls into three categories: descriptive, administrative and structural. Descriptive metadata supports discoverability and categorization. To use the library analogy, this is the book’s title, synopsis, theme, etc. It’s the information that helps you find what it is you’re looking for.
Administrative metadata provides details about stewardship and maintenance. This is how to check the book out of the library and what you’re allowed to do with it. Without this information, you won’t be able to confidently use the information you find.
Structural metadata describes the relationships between things. In our book analogy, this is a glossary and index, and also a book’s earlier drafts, translations, page count, and sources.
"Metadata management" is the act of organizing all this metadata to achieve the maximum benefit. Good metadata management makes it easier to find data, apply and adhere to governance rules and interpret and analyze data.