The Full Form of GID is‍ Governments Integrated Directory.

The purpose of this collection is to provide a current and comprehensive database of U.S.
state and local governments, and their major agencies for statistical program use. The
United States Code Title 13 Section 161 authorizes the U.S. Census Bureau to conduct
this program.

All state and independent local governments are represented including counties,
municipalities, townships, school districts, and special districts. As enumerated for the
2007 Census of Governments there were 89,526 of these entities. In addition major
agencies of these governments are covered when needed for Census operations.
The following paragraphs summarize the characteristics for each of the five major types
of local governments. See “Criteria for Classifying Governments,” below, for a
statement of the criteria used for the classification of governments in census statistics on
governments. See the individual state descriptions for an application of these criteria to
the local governmental structure in each state.