We pick f.root-servers.net, one of the 13 root servers (1), and ask it about terralycos.com and learn that com is delegated to 13 name servers (2), so we ask c.gtld-servers.net and get the following answer:
Terralycos.com is a domain controlled by three domain name servers at terra.com. Two domain name servers have the same IP number. Both are on different IP networks. Incoming mail for terralycos.com is handled by one mail server at terra.es.