A top-level domain (TLD) is one of the domains at the highest level in the hierarchical Domain Name System of the Internet after the root domain. The top-level domain names are installed in the root zone of the name space. For all domains in lower levels, it is the last part of the domain name, that is, the last non empty label of a fully qualified domain name. For example, in the domain name www.example.com, the top-level domain is .com. Responsibility for management of most top-level domains is delegated to specific organizations by the ICANN, an Internet multi-stakeholder community, which operates the Internet Assigned Numbers Authority (IANA), and is in charge of maintaining the DNS root zone.
In the Internet, a domain name is a string that identifies a realm of administrative autonomy, authority or control. Domain names are often used to identify services provided through the Internet, such as websites, email services and more. As of 2017, 330.6 million domain names had been registered. Domain names are used in various networking contexts and for application-specific naming and addressing purposes. In general, a domain name identifies a network domain or an Internet Protocol (IP) resource, such as a personal computer used to access the Internet, or a server computer.
A domain name registry is a database of all domain names and the associated registrant information in the top level domains of the Domain Name System (DNS) of the Internet that enables third party entities to request administrative control of a domain name. Most registries operate on the top-level and second-level of the DNS.
The domain com is a top-level domain (TLD) in the Domain Name System (DNS) of the Internet. Created in the first group of Internet domains at the beginning of 1985, its name is derived from the word commercial, indicating its original intended purpose for subdomains registered by commercial organizations. Later, the domain opened for general purposes.
The Internet uses the Domain Name System (DNS) to associate numeric computer IP addresses with human-readable names. The top level of the domain name hierarchy, the DNS root, contains the top-level domains that appear as the suffixes of all Internet domain names. The most widely used DNS root is administered by the Internet Corporation for Assigned Names and Numbers (ICANN). In addition, several organizations operate alternative DNS roots, often referred to as alt roots. These alternative domain name systems operate their own root name servers and commonly administer their own specific name spaces consisting of custom top-level domains.
A country code top-level domain (ccTLD) is an Internet top-level domain generally used or reserved for a country, sovereign state, or dependent territory identified with a country code. All ASCII ccTLD identifiers are two letters long, and all two-letter top-level domains are ccTLDs.
.sa is the Latin alphabet Internet country code top-level domain (ccTLD) of Saudi Arabia. Domains of this type can be registered through SaudiNIC, a department of the Communications and Information Technology Commission. The Arabic alphabet ccTLD of Saudi Arabia is السعودية.
.il is the Internet country code top-level domain (ccTLD) of Israel, administered by the Israel Internet Association and managed by NIC - ISRAEL, which hosts the DNS root server and manages the Israeli Internet Exchange, that supports IPv4 and IPv6.
.um was the Internet country code top-level domain for the United States Minor Outlying Islands. It was administered by the United States Minor Outlying Islands Registry. Until late 2006 USMIR was housed at the University of Southern California Information Sciences Institute (USC-ISI), which was the original administrator of .us prior to NeuStar absorbing that role.
.in is the Internet country code top-level domain (ccTLD) for India. It was made available in 1989, four years after original generic top-level domains such as .com, .net and the country code like .us. It is currently administered by the National Internet Exchange of India (NIXI).
.ir is the Internet country code top-level domain (ccTLD) for Iran. It is managed by the Institute for Research in Fundamental Sciences.
.ky is the Internet country code top-level domain (ccTLD) for the Cayman Islands. The code was chosen as other possible options had already been allocated. Registration was limited to residents and registered companies in the Cayman Islands with a local address, but this restriction was removed in September 2015. The Cayman Islands also has the international three-letter code CYM and has won a bid to be awarded the .cym domain in a future expansion of the top-level domain space.
.so is the internet country code top-level domain (ccTLD) for Somalia. After a long absence, the .so domain was officially relaunched on November 1, 2010, by .SO Registry, which is regulated by the nation's Ministry of Posts and Telecommunications. It was launched through various accredited registrars around the world.
.pa is the Internet country code top-level domain (ccTLD) for Panama. It was first registered in 1994-05-25. It is administered by NIC Panamá, which is run by the Universidad Tecnologica de Panama.
The Domain Name System of the Internet consists of a set of top-level domains that constitute the root domain of the hierarchical name space and database. In the growth of the Internet, it became desirable to expand the initial set of six generic top-level domains in 1984. As a result, new top-level domain names have been proposed for implementation by ICANN. Such proposals included a variety of models ranging from adoption of policies for unrestricted gTLDs that could be registered by anyone for any purpose, to chartered gTLDs for specialized uses by specialized organizations. In October 2000, ICANN published a list of proposals for top-level domain strings it had received.
A geographic top-level domain is any of an unofficial group of top-level domains in the Domain Name System of the Internet using the name of or invoking an association with a geographical, geopolitical, ethnic, linguistic or cultural community. The IANA does not recognize these domains as their own group within the Root Zone Database, rather classifying them as generic top-level domains.
The domain name .рф is the Cyrillic country code top-level domain for the Russian Federation, in the Domain Name System of the Internet. In the Domain Name System it has the ASCII DNS name xn--p1ai. The domain accepts only Cyrillic subdomain applications, and is the first Cyrillic implementation of the Internationalizing Domain Names in Applications (IDNA) system. The domain became operational on 13 May 2010. As of 2014 it is the most used internationalized country code top-level domain, with around 900,000 domain names.
An internationalized country code top-level domain is a top-level domain in the Domain Name System (DNS) of the Internet. IDN ccTLDs are specially encoded domain names that are displayed in an end user application, such as a web browser, in their language-native script or alphabet, such as the Arabic alphabet, or a non-alphabetic writing system, such as Chinese characters. IDN ccTLDs are an application of the internationalized domain name system to top-level Internet domains assigned to countries, or independent geographic regions.
.ss is the designated country code top-level domain (ccTLD) for South Sudan in the Domain Name System of the Internet. It is derived from the ISO 3166-1 alpha-2 code for South Sudan, which is SS. According to CIO East Africa, the TLD was allocated on 10 August 2011 following the country's declaration of independence from Sudan. The TLD was registered on 31 August 2011, but not added to the DNS root zone and was thus not operational. It was approved at the ICANN Board meeting on 27 January 2019 and was added to the DNS root zone on 2 February 2019.
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