A DNS server houses the IP addresses used to access internet resources. The internet operates via IP address in the format of 255.255.255.255 (i.e. 192.168.002.015). Since those are hard to remember, DNS servers are responsible for translating the user friendly names like www.faqfarm.com to 64.255.154.135. I think there are something like 7 hub DNS servers on the internet that replicate to all the rest (happens constantly).
