.us is the Internet country code top-level domain (ccTLD) for the United States. It was established in early 1985. Registrants of .us domains must be U.S. citizens, residents, or organizations – or foreign entities with a presence in the United States or any territory of the United States. Most registrants in the U.S. have registered for .com, .net, .org and other gTLDs, instead of .us, which has primarily been used by state and local governments, even though private entities may also register .us domains. The domain is managed by Registry Services, LLC, a domain name registry, on behalf of the United States Department of Commerce.
.ca is the Internet country code top-level domain (ccTLD) for Canada. The domain name registry that operates it is the Canadian Internet Registration Authority (CIRA).
.uk is the Internet country code top-level domain (ccTLD) for the United Kingdom. It was first registered in July 1985, seven months after the original generic top-level domains such as .com and the first country code after .us.
.pr is the Internet country code top-level domain (ccTLD) for Puerto Rico.
.ar is the Internet country code top-level domain (ccTLD) for Argentina. It is administered by NIC Argentina. Registering an .ar domain directly is allowed as of 2020. Previously, only 9 of the second-level domains listed below were open for registration, and a local presence in Argentina was required. Recently the extension has become synonymous with Augmented Reality and is being by many prominent AR and XR startups.
.br is the Internet country code top-level domain (ccTLD) for Brazil. It was administered by the Brazilian Internet Steering Committee until 2005 when it started being administered by Brazilian Network Information Center. A local contact is required for any registration. Registrations of domain names with Portuguese characters are also accepted.
.jp is the Internet country code top-level domain (ccTLD) for Japan. It was established in 1986 and is administered by the Japan Registry Services.
.za is the Internet country code top-level domain (ccTLD) for South Africa. The .za namespace is managed and regulated by the .za Domain Name Authority (ZADNA). Most domains are registered under the second-level domain .co.za.
.cu is the country code top-level domain (ccTLD) for Cuba.
.et is the country code top-level domain (ccTLD) for Ethiopia. Ethiotelecom offer top-levels domains as second- and third-level domains.
.ug is the Internet country code top-level domain (ccTLD) for Uganda.
.mo is the Internet country code top-level domain (ccTLD) for Macau.
.tr is the Internet country code top-level domain (ccTLD) for Turkey. It is administered by trABİS and managed by the Computer Center DNS Group of the ICT Authority. The domain was formerly administered by NIC.tr and managed by the Turkey Internet Society until September 2022.
.mx is the Internet country code top-level domain (ccTLD) for Mexico, which in 2009 was re-opened to new registrations by NIC México. In 2009, the .mx ccTLD was rolled out in three steps:
.sv is the Internet country code top-level domain (ccTLD) for El Salvador.
.sy is the Internet country code top-level domain (ccTLD) for Syria. The registry is operated by the National Agency for Network Services. It took over from the Syrian Telecommunications Establishment in 2011.
.tj is the Internet country code top-level domain (ccTLD) for Tajikistan. Registrations are processed via accredited registrars.
.tz is the Internet country code top-level domain for Tanzania. Through a consultative process, Tanzania Network information Centre (tzNIC), a not-for-profit company was established and registered to administer and manage the operations of the Tanzania country code top-level domain. tzNIC is a limited company with two founding members – the Tanzania Communication Regulatory Authority and the Tanzania Internet Service Provider Association.
In the Domain Name System (DNS) hierarchy, a second-level domain is a domain that is directly below a top-level domain (TLD). For example, in example.com, example is the second-level domain of the .com TLD.
.rs is the Internet country code top-level domain (ccTLD) for Serbia. The domain name registry that operates it is the Serbian National Internet Domain Registry (RNIDS). The letters rs stand for Republika Srbija/Република Србија.
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