Hello,

DNS is critical to the operation of the Internet. When you enter www.some-domain.com in a Web browser, it's DNS that takes the www host name and translates it to an IP address. Without DNS, you could be connected to the Internet just fine, but you ain't goin' no where. Not unless you keep a record of the IP addresses of all of the resources you access on the Internet and use those instead of host/domain names.

So when you visit a Web site, you are actually doing so using the site's IP address even though you specified a host and domain name in the URL. In the background your computer quickly queried a DNS server to get the IP address that corresponds to the Web site's server and domain names. Now you know why you have to specify one or two DNS server IP addresses in the TCP/IP configuration on your desktop PC (in the resolv.conf file on a Linux system and the TCP/IP properties in the Network Control Panel on Windows systems).

A "cannot connect" error doesn't necessarily indicate there isn't a connection to the destination server. There may very well be. The error may indicate a failure in "resolving" the domain name to an IP address. I use the open source Firefox Web browser on Windows systems because the status bar gives more informational messages like "Resolving host", "Connecting to", and "Transferring data" rather than just the generic "Opening page" with IE. (It also seems to render pages faster than IE.)

Hope this helps.