What is whois command in Linux?
whois command is a query and response protocol, used to fetch the contact details, creation and expiration date, address of the registered domains, websites and IP address.
By default , In Linux whois command format/syntax is,
whois [OPTION]... OBJECT...
In your terminal, type as whois and hit enter. This will automatically show the usage format and all the options of commands. It is shown in the below image.