This server provides metadata through the National Geospatial Data Clearinghouse, a distributed catalog of geospatial data sets from numerous Federal, state, and private-sector agencies. Although the primary interface to this information is the searchable catalog, the records available here are also available using simple web interfaces as a convenience to web users who chance upon this page.
Metadata are data about data.
Here the term refers to geospatial metadata , meaning information about geospatial data such as images of the earth, maps and the geographical features that maps represent. Geospatial metadata are structured in a consistent way so that once you get used to the format, like cards in a library catalog, it becomes easy to find what you need.