is a reserved

top-level domain A top-level domain (TLD) is one of the domain name, 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 DNS root zone, root zone of the nam ...

used to test

websites A website (also written as a web site) is any web page whose content is identified by a common domain name and is published on at least one web server. Websites are typically dedicated to a particular topic or purpose, such as news, education ...

web applications A web application (or web app) is application software that is created with web technologies and runs via a web browser. Web applications emerged during the late 1990s and allowed for the server to dynamically build a response to the request, ...

as an alternative to testing webpages using the default

localhost In computer networking, localhost is a hostname that refers to the current computer used to access it. The name ''localhost'' is reserved for loopback purposes. It is used to access the network services that are running on the host via t ...

. It is guaranteed to never be registered into the Internet. Along with , there are 11 other reserved test domains: , , , , , , , , , , and .

Reserved DNS names

In June 1999, the

Internet Engineering Task Force The Internet Engineering Task Force (IETF) is a standards organization for the Internet standard, Internet and is responsible for the technical standards that make up the Internet protocol suite (TCP/IP). It has no formal membership roster ...

reserved the DNS labels , , , and so that they may not be installed into the root zone of the Domain Name System. These top-level domain names were reserved to reduce the likelihood of conflict and confusion. This allows their usage for either documentation purposes or in local testing scenarios. IANA.org states "Domains which are described as registered to IANA or ICANN on policy grounds are not available for registration or transfer, with the exception of .info domains. These domains are available for release by the ICANN Governmental Advisory Committee Secretariat."

References

Top-level domains Internet properties established in 1999 {{compu-domain-stub sv:Toppdomän#Generiska toppdomäner