WHOIS is a query and response protocol listening on TCP port 43 to query databases containing internet resources' registered users or assignees. These resources include domain names, IP addresses, and autonomous systems, but it is also used for a wider range of other information.
:::info The WHOIS Protocol Specification can be found at RFC3912. :::
You can use this tool with CLI (e.g., whois) or some online versions like .
export TARGET="facebook.com"
whois $TARGET