Metadata is data about data. An item of metadata may describe an individual datum, or content item, or a collection of data including multiple content items.
Metadata (sometimes written ‘meta data’) is used to facilitate the understanding, use and management of data. The metadata required for effective data management varies with the type of data and context of use. In a library, where the data is the content of the titles stocked, metadata about a title would typically include a description of the content, the author, the publication date and the physical location. In the context of a camera, where the data is the photographic image, metadata would typically include the date the photograph was taken and details of the camera settings. In the context of an information system, where the data is the content of the computer files, metadata about an individual data item would typically include the name of the field and its length. Metadata about a collection of data items, a computer file, might typically include the name of the file, the type of file and the name of the data administrator.~ Wikipedia
PACA releases metadata standards
Mastering Metadata
[youtube=http://www.youtube.com/watch?v=sdLg-tWum9E]
Metatdata on steroids
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