top-level domain

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top-level domain

The last and most significant component of an Internet fully qualified domain name, the part after the last ".". For example, host is in top-level domain "uk" (for United Kingdom).

Every other country has its own top-level domain, including ".us" for the U.S.A. Within the .us domain, there are subdomains for the fifty states, each generally with a name identical to the state's postal abbreviation. These are rarely used however. Within the .uk domain, there is a subdomain for academic sites and a domain for commercial ones. Other top-level domains may be divided up in similar ways.

In the US and some other countries, the following top-level domains are used much more widely than the country code:

.com - commercial bodies .edu - educational institutions .gov - U. S. government .mil - U. S. armed services .net - network operators .org - other organisations

Since the rapid commercialisation of the Internet in the 1990s the ".com" domain has become particularly heavily populated with every company trying to register its company name as a subdomain of .com, e.g. "" so as to make it easy for customers to guess or remember the URL of the comany's home page.

United Nations entities use the domain names of the countries where they are located. The UN headquarters facility in New York City, for example, is

Several new top-level domains are about to be added (Oct 1997): .nom - individual people .rec - recreational organisations .firm - businesses such as law, accounting, engineering .store - commercial retail companies .ent - entertainment facilities and organisations
References in periodicals archive ?
The idea is that private companies or organizations could invest in their own generic top-level domain either for a specific community, or for more general public use.
Although ICANN added seven domains in 2000 and plans to add up to 10 more in 2005, the report also indicates that ICANN should strengthen its agreements with top-level domain operators to help ensure that they do not ignore agreed-upon standards or practices.
WHEN THE INTERNET Corporation for Assigned Names and Numbers (ICANN) released its list of seven new top-level domains last summer, critics of the government-sanctioned corporation complained the new options were too limited.
Despite a certain amount of controversy, this past fall the Internet Corporation for Assigned Names and Numbers (ICANN) selected seven new registries for top-level domains (TLDs), including one aimed at professionals like CPAs--the "dot-pro" designation.
ICANN has been considering creating additional generic top-level domain names, such as .
Several other "last names"--called top-level domains (TLDs)--exist, such as .
Late last year, ICANN recommended that seven new top-level domains be adopted, including .
SITA, a Swiss-based provider of integrated telecomms and information systems for the air transport industry, claims it has received widespread industry support for its proposal to create an air transport community specific top-level domain - '.
A top-level domain is the final Internet suffix that can identify an e-mail account's or World Wide Web site's country of origin, as in www.