There is no agreed upon definition of metadata. Here are a few established definitions:
- "Structured data about an object that supports functions associated with the designated object" (Greenberg, 2003)
- "Structured information that describes, explains, locates, or otherwise makes it easier to retrieve, use, or manage an information resource." (NISO, 2004)
- "Digital object as an instance of an abstract data type that has two components, data and key-metadata. The key-metadata includes a handle, i.e. an identifier globally unique to the digital object." (Kahn and Wilensky, 1995)
- "Metadata can be defined as a structured description of the essential attributes of an information object." (Hill, 2016) 
- "Metadata are structure, encoded data that describe the characteristics of information-bearing entities to aid in the identification, discovery, assessment and management of the described entities." (Smiraglia, 2005) 
- "Perhaps a more useful, ‘big picture’ way of thinking about metadata is as the sum total of what one can say about any information object at any level of aggregation. In this context, an information object is anything that can be addressed and manipulated as a discrete entity by a human being or an information system" (Gilliland, 2016) 
- "Metadata is a map. Metadata is a means by which the complexity of an object is represented in a simpler form. Metadata is a statement about a potentially informative object." (Pomerantz, 2015) 
- "Metadata in this context is the information that accompanies the various stages and outputs of research." (Gregg, 2020) 
- "Metadata is a love note to the future." (Jason Scott, 2011) 
Purpose of metadata
"Metadata supply chain"
EERAdata Metadata Creator
The Metadata Creatoris an easy-to-use tool provided by the EERAdata Community Platform to support creating metadata in a standard schema for a given data object. It allows to download this metadata in a machine-readable file format (JSON-LD) to improve the FAIR status of the data object. Moreover, the metadata is stored in the searchable repository on the EERAdata platform, improving the findability of the data object.
- Greenberg, J. (2003), “Metadata and the World-Wide-Web”, Encyclopedia of Library and Information Science, pp. 1876–88
- NISO (2004) https://www.niso.org/publications/understanding-metadata-2017
- Kahn and Wilensky (1995) http://www.cnri.reston.va.us/k-w.html
- Tony Hill In M. Baca, Introduction to Metadata, Getty Publishing, 2016
- Richard P. Smiraglia, Metadata: A A Cataloger's Primer, Psychology Press, 2005
- A.J. Gilliland In M. Baca, Introduction to Metadata, Getty Publishing, 2016
- Jeffrey Pomerantz, Metadata, MIT press, 2015
- Gregg, W. et al., A literature review of scholarly communications metadata. Research Ideas and Outcomes 5.