ummm

This form will perform various NSlookups (Name Server lookups) to find out various information about a particular host or domain name. By entering a domain name below, you can find out the domains name, web, mail and ftp servers. It tries to intelligently guess if you entered in a domain or host too.

Below the domain is the SPF (Sender Policy Framework) entries that can tell mail servers where email for the domain should be coming from.