If you spend any time on the Internet sending
e-mail or browsing the Web, then you use
domain name servers without even realizing it. Domain name servers, or DNS, are an incredibly important but completely hidden part of the
Internet, and they are fascinating. The DNS system forms one of the largest and most active distributed databases on the planet. Without DNS, the Internet would shut down very quickly.
When you use the Web or send an e-mail message, you use a
domain name to do it. For example, the URL "http://www.
howstuffworks.com" contains the domain name
howstuffworks.com. So does the e-mail address "iknow@howstuffworks.com."
Human-readable names like "howstuffworks.com" are easy for people to remember, but they don't do machines any good. All of the machines use names called
IP addresses to refer to one another. For example, the machine that humans refer to as "www.howstuffworks.com" has the IP address
70.42.251.42. Every time you use a domain name, you use the Internet's domain name servers (DNS) to translate the human-readable domain name into the machine-readable IP address. During a day of browsing and e-mailing, you might access the domain name servers hundreds of times!