When referring to an Internet address or name a domain or domain name is the location of a website. For example, the domain name "google.com" points to the IP address "184.108.40.206", but it is generally easier to remember a name rather than a long string of numbers. A domain name can be a maximum of sixty-three characters with one character minimum, and is entered after the protocol in the URL, as you can see in the following example.
Domains, like most brilliant ideas, work on more than one level. They include both a top level domain and a second level domain. And, like brilliant ideas, they also center around a single point—or in this case, a dot.
|.com||commercial||Verisign||This is an open TLD; any person or entity is permitted to register. Though originally intended for use by for-profit business entities, for a number of reasons it became the "main" TLD for domain names and is currently used by all types of entities including nonprofits, schools, and private individuals. Domain name registrations may be successfully challenged if the holder cannot prove an outside relation justifying reservation of the name, to prevent "squatting". It was originally administered by the United States Department of Defense.||Yes||Yes|
|.org||organization||Public Interest Registry||This is an open TLD; any person or entity is permitted to register. Originally intended for use by non-profit organizations, and still primarily used by some.||Yes||Yes|
|.net||network||Verisign||This is an open TLD; any person or entity is permitted to register. Originally intended for use by domains pointing to a distributed network of computers, or "umbrella" sites that act as the portal to a set of smaller websites.||Yes||Yes|
|.int||international organizations||Internet Assigned Numbers Authority||The .int TLD is strictly limited to organizations, offices, and programs endorsed by a treaty between two or more nations. However, a few grandfathered domains do not meet these criteria.||No||Yes|
|.edu||education||Educause (via Verisign)||The .edu TLD is limited to specific higher educational institutions such as, but not limited to, trade schools and universities. In the U.S., its use was restricted in 2001 to post-secondary institutions accredited by an agency on the list of nationally recognized accrediting agencies. This domain is therefore almost exclusively used by American colleges and universities. Some institutions, such as the Exploratorium, that do not meet the current registration criteria have grandfathered domain names.||No||Yes|
|.gov||U.S. national and state government agencies||General Services Administration (via Verisign)||The .gov TLD is limited to United States governmental entities and agencies as well as qualifying state, county and local municipal government agencies.||No||Yes|
|.mil||U.S. military||United States Department of Defense||The .mil TLD is limited to use by the United States military.|
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