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Definition: Internet domain name


An Internet domain name is a unique name of a server connected to the Internet, such as a Web server, email server or FTP (file transfer) server. Internet domain names are often the name of an organization such as Apple.com and Microsoft.com; however, a name can refer to any publication or service, virtually anything. By 2024, there were more than 350 million registered domain names.

The name is combined with a generic top-level domain (gTLD), such as .com or .org. For example, computerlanguage.com is the domain name for the publisher of this encyclopedia.

Under ICANN's "New gTLD" program, communities, industries and organizations can create their own top-level domain names (see New gTLD).

Registration Is Required
In order for a domain name to be visible on the Internet, it must first be registered with any one of hundreds of registrars, which will verify that the name is absolutely unique. See registrar.

Dub-Dub-Dub or Whatever
In order to access The Computer Language Company website, www.computerlanguage.com is typed into the browser's address bar (see URL). The WWW, often verbalized as "dub-dub-dub," is a mnemonic commonly used for the hostname of a company's Web server. However, WWW is only a recommendation, and Web servers can be assigned any hostname. In addition, most companies configure their Web servers to default to WWW. For example, computerlanguage.com without the WWW is sufficient. See hostname and DNS.

Different mnemonics are also widely used to identify sections of a site; for example, support.computerlanguage.com could be a valid address, in which case the word SUPPORT could not be omitted when typing the name.

Generic Top-Level Domains
In 1985, the following generic top-level domains (gTLDs) were created.
  Unrestricted gTLDs

 .com   commercial
 .net   network oriented
 .org   non-profit organization

  Restricted gTLDs

 .edu   accredited U.S. educational
 .gov   U.S. government agencies
 .mil   U.S. military
 .int   international treaties (1988)


More Domain Names
Starting in 2000, ICANN added more domains. Sponsored domains means that their use is reserved for a particular community, or registration is restricted to a certain type of applicant (see sTLD).

  Sponsored Top-Level Domains

  sTLD    Purpose

 .aero    global aviation community
 .asia    Pan-Asia/Asia Pacific region
 .cat     Catalan community
 .coop    cooperatives
 .jobs    human resources/employment
 .mobi    mobile products/services
 .museum  museums
 .post    postal sector
 .pro     licensed professionals
 .tel     contacts (see .tel)
 .travel  travel industry
 .xxx     X-rated


  Unsponsored Top-Level Domains

 .biz     businesses
 .info    information service
 .name    individuals


Countries Also Have Domain Names
Every country has a top-level domain; for example, .ca for Canada and .fr for France. The U.S. country code is .us, but it is not widely used. See country code, New gTLD, ICANN, IP address and FQDN.