Metadata

Definition

Metadata is data linked to some data item, i.e., metadata is data about data. The metadata of a data item specifies how the data item was created, in which context it can be used, how it was transformed, or how it can be interpreted or processed. The earliest use of metadata are bibliographic records about books, such as the author of the book. In principle, any type of data item can have metadata attached to it. The type of the data item itself can be metadata and determines which other metadata fields may be attached to the data item.

Key Points

The purpose of metadata is to provide contextual information for a data item. It may be used by humans to determine the usability of a data item. Likewise, computer programs can read the metadata in order to guide the processing of a data item. Metadata can be included in the data item (e.g., the date and location of a photography), or it may be stored apart of the data item. In the latter case, the data item requires being...