In the context of USGIN data-sharing networks such as the National Geothermal Data System (NGDS), metadata is used to describe and keep track of three different kinds of data resources:

• Geoscience data that has been hosted as a web service
• Geoscience data that has been uploaded to a USGIN document repository
• Geoscience data from another online source, such as a university or corporation

Metadata records (often stored in databases) populate a metadata catalog, such as the NGDS Catalog, where they are used to locate and access the data resources they describe. By sifting through metadata records, it is possible to find the data resources described by these metadata records, even though USGIN is a distributed network.

This concludes the USGIN Metadata Tutorial.