Whois is a protocol for retrieving information about IP-addresses and internet domains. It was defined in RFC 3912. These information include statements of ownership and responsibility.
Some operating systems deliver a command line tool for using this information as well.
Usage is easy:
> whois information-information.de
or IP-based
> whois 3.144.109.104
The result indicates technical information about owner, contacts, and even contact addresses. However since recent privacy updates (like GDPR) most data (like domain owner) needs to be hidden, rendering the whois entry basically useless for open public use.
However the data is still available to authorized parties.
