.onion

The ending used for services inside the Tor network, which hides where a service is hosted. The IETF (glossary)IETF Internet Engineering Task Force The open body that writes internet standards such as DNS, EPP and RDAP. Full definition of IETF reserved it as a special-use name in 2015, so it is never looked up in the DNS (glossary)DNS Domain Name System The internet's directory that links domain names to computer addresses. Full definition of DNS and is not part of the DNS root. Only Tor software can reach these addresses.