The domain name WHOIS system is a public database of contact information associated with each domain name. The manager for each Top Level Domain (.org, .com, .ninja) manages the WHOIS directory for their respective TLD.
The WHOIS directory keeps contact information for the owner of a domain name, including:
name
phone number
mailing address
email address
Naturally, this is directory is a prime target for marketers. Because of this, many domain name owners choose to use WHOIS privacy.
For more information on the WHOIS system, see the WHOIS chapter of the Ultimate Domain Name Guide
