domainsofnote.com

Whatis Whois?

When you register a domain name, the details you register with are stored in a database called WhoIs.

This basically allows anyone to view and have a look around at who owns which domain and provides them with some (if fairly limited) point of contact.

You can check Whois to view domain expiration dates (if you want to buy a domain form someone), check who a registrar of a domain is.

Having your private contact details on Whois can leave you vulnerable to data miners, spam, bots, and all sorts of nasty people, so its a good idea to at least look over your whois after buying a domain and removing any info you want through your domain control panel.