WHOIS
A protocol + service that returns the registration record for a domain — registrar, creation/expiry dates, and (historically) the owner's contact details.
Privacy era
GDPR + ICANN’s 2018 redaction policy mean most public WHOIS responses now hide the registrant’s name and email behind ‘Redacted for Privacy’. Authorized parties (law enforcement, IP holders) can request unredacted data via RDRS.
What’s still public
Registrar, creation date, expiry date, and nameservers stay visible — useful for verifying a domain’s age + active registration.