Geospatial metadata (data about data) consistently describes datasets (collections of spatial data). This enables effective management and availability of that data. Each online dataset description forms an interface to the actual data and to more information about it.
See also: IndexGeo / Geospatial metadata / About metadata
Metadata is data about data. A dataset description is a metadata document, describing the data, but is not the actual data itself.
The dataset description document is well-defined and structured using elements of metadata. It is analogous to a card in the catalogue of your local library which describes the books and gives enough information to know what the book is called, its unique number, how and where to find it. These details are metadata - bibliographic elements such as Author, Title, Abstract.
Geospatial dataset descriptions describe spatial data, data that has reference to a location in earth-centred space.
Geospatial dataset descriptions are composed of well-defined metadata elements which have a specific structure and order. The dataset descriptions are maintained as documents in the Standard Generalised Markup Language (SGML).
Importantly, the document must conform to the Document Type Definition (DTD) which defines the allowed elements and their order and structure. The DTD is "used to automatically process a document ... and check that all of the elements required for that document are indeed present and correctly ordered" [from A Gentle Introduction to SGML].
The ANZMETA DTD defines geospatial datasets in Australia and New Zealand.
Geospatial metadata has many uses, including:
Last Modified: 26 May 2000