What is Metadata?

Metadata is structured information that describes, explains, locates or otherwise makes is easier to retrieve, use or manage an information resource. Metadata is often called data about data or information about information.

Having no metadata is like an unlabeled steel can. Without knowledge of its provenance the only way to determine content and appropriate use would be to open it, subject it to analysis, measurement and expert judgement. Like the information given on a food label, metadata is given in a standard format so that no matter what label you are looking at, you know that it has to give certain information.

In the area of geospatial information (information with a geographic component) this normally means the What, Who, Where, When and How of the data. The only major difference between geographic metadata and the many other metadata sets being created for libraries, academia, professions, etc, is the emphasis on the spatial component - the 'where' element.

Why is Metadata important?

In the ACIL Tasman report , prepared for the CRC for Spatial Information and released in March 2008, it was found that:

  • Australian Government agencies spent around $85 million on spatial data production and management in 2006-07.
  • 67% of agencies expected to reduce costs significantly due to improved business processes and 64% expected to reduce staff costs and other direct costs.
  • estimated inefficient access to data reduced the direct productivity of some sectors in Australia by between 5% and 15%

With increasing amounts of data being created and stored (but sometimes not organised) there is a real need to document the data for future use - to be as accessible as possible to as wide a "public" as possible. There are significant benefits in doing so:

  • Metadata helps organise and maintain an organisation's investment in data.
  • It provides information about an organisation's data holdings in catalogue form or to potential external users of the data.
  • Accessible metadata records help to avoid duplication of effort by ensuring awareness of the existence of datasets, and promote the availability of geospatial data beyond the traditional geospatial community.
  • Users can locate all available geospatial data relevant to an area of interest or study. There is increasing pressure from customers for easier and quicker access to the right information, at little or no charge.
  • Properly constructed metadata allows a potential user to make an informed decision about the fitness of the data for purpose he intends to put it to.
  • Data providers are able to advertise and promote the availability of their data via online services.
  • Metadata supports machine to machine operations and facilitates interoperability.
  • Metadata supports the archiving and preservation of valuable resources and provides guidance on integration of legacy resources into current systems where necessary.

When users have a choice between two sets of data it is likely that resources without metadata will be relegated second class, or not considered further at all. They are more likely to be abandoned for options with reliable, maintained metadata. The undocumented data may be of far higher quality but without metadata how would you know?

OSDM has been working in conjunction with ANZLIC - the Spatial Information Council to produce tools and educational information to facilitate the location and access of spatial data and services. More information can be obtained from the ANZLIC Website www.anzlic.org.au/metadata  

NOTE  If you are an Australian Government employee, you can access more information about metadata activities in the Members' Only section of the OSDM website.