What is the NSDI?

FGDC LogoThe National Spatial Data Infrastructure

Ask 20 people to define the National Spatial Data Infrastructure and you are likely to get 20 definitions that vary in scope, application, responsibility, and format. Most would agree, however, that the NSDI consists of:

The NSDI is a cooperative effort involving federal, state, and local government, the private sector, and academia. The Federal Geographic Data Committee is charged through a Presidential Executive Order with providing the federal leadership for evolving the NSDI.

The formal definition of National Spatial Data Infrastructure (NSDI) is an umbrella of policies, standards, and procedures under which organizations and technologies interact to foster more efficient use, management, and production of geographic, or spatial, data.


Current and accurate spatial data will be readily available to contribute locally, nationally, and globally to economic growth, environmental quality and stability, and social progress.


Major Components of the NSDI

The National Geospatial Data Clearinghouse

The fourth component, the means to search, query, and find geographic data is the basis for the National Geospatial Data Clearinghouse. The Clearinghouse is a distributed, electronically connected network of spatial data producers, managers, and users.

The Clearinghouse is not a central repository where data sets are stored, but rather a comprehensive listing of data being produced by government agencies, universities, utilities, and many other organizations around the country. The data listing is augmented by a structured summary of information about the data or metadata.


Metadata, sometimes called "data about data", describe the content, quality, condition, and other characteristics of data. It is through the evaluation of the metadata that a user can determine if the data meets the user's needs. Metadata describe different aspects of data, including:

Identification -- What is the name of the data set? who developed the data set? What geographic area does it cover? What themes of information does it include? How current are the data? Are there restrictions on accessing or using the data?

Data Quality -- How good are the data? Is information available that allows a user to decide if the data are suitable for his or her purpose? What is the positional and attribute accuracy? Are the data complete? Were the consistency of the data verified?

Entity and Attribute Information -- What geographic information (roads, houses, elevation, temperature, etc.) is included? How is the information encoded? Were codes used? What do the codes mean?

Distribution -- From whom can I obtain the data? What formats are available? What media are available? Are the data available online? What is the price of the data?

North Carolina Geographic Data Clearinghouse

The North Carolina Geographic Data Clearinghouse is a part of this national effort.

Sources of Information

If you'd like additional information, click here to get Geographic Information Resources.

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