When you use the Web or send an e-mail message, you use a domain name to do it. For example, theUniform Resource Locator (URL) "http://www.howstuffworks.com" contains the domain name howstuffworks.com. So does this e-mail address: example@howstuffworks.com. Every time you use a domain name, you use the Internet's DNS servers to translate the human-readable domain name into the machine-readable IP address. Check out How Domain Name Servers Work for more in-depth information on DNS