.gov is a sponsored top-level domain restricted for use by government entities in the United States. The .gov domain is administered by the General Services Administration (GSAThe U.S. is the only country that has a government-specific top-level domain in addition to its country-code top-level domain, due to the origins of the Internet as a U.S. federal government-sponsored research network (see National Science Foundatio Network and ARPANET).
Other countries typically use a second-level domain for this purpose (such as .gov.ar for Argentina, .gov.au for Australia, .gc.ca for Canada, .gouv.fr for France, .gov.in for India, .gov.my for Malaysia, .govt.nz for New Zealand, .guv.ro for Romania, .gov.uk for the United Kingdom, .gub.uy for Uruguay, .gov.za for South Africa).
Some U.S. federal agencies use .fed.us rather than .gov. The Department of Defense and its subsidiary organizations use .mil. Some U.S. governmental entities use other domains, such as the use of .com domains by the United States Postal Service (whih uses both usps.gov and usps.com for the same location, although it only advertises the .com version) and the United States Army's recruitment website (goarmy.com, this trend is repeated at the recruitment websites of the other branches of the U.S.
Additionally, some technically private organizations having some formal association with the federal government make use of .gov, such as the quasi-public Federal Reserve System (federalreserve.gov).
All governments in the U.S. are allowed to apply for use of .gov, such as atlantaga.gov for the city of Atlanta, loudoun.gov for the county of Loudoun, Virginia and georgia.gov for the U.S. state of Georgia. This was not always true; under an earlie policy, only federal agencies were allowed to use the domain, and agencies beneath cabinet level were required to use subdomains of their parent agency.
There is a lack of consistency in addresses of state and local government sites, with some using .gov, some .us, some using both (the Commonwealth of Virginia uses both www.state.va.us and www.virginia.gov for the same location) and still others in .com, .org or other TLDs.
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