The WHOIS is a query/response protocol that is widely used to query databases that hold information about internet resources such as domain names and IP address allocations.

Created in the 1980s, WHOIS began as a service used by Internet operators to identify individuals or entities responsible for the operation of a network resource on the Internet. The WHOIS service has since evolved into a tool used for many purposes.

Nowadays the WHOIS protocol is primarily used by registrants and users to query domain registrar databases to obtain domain name information and check domain name availability. (continue →)