What is a domain name?
Each domain name corresponds to numeric IP (Internet Protocol) addresses. An IP address takes the form of 4 numbers, each one between 0 and 255, separated by periods.
The Internet uses the numeric IP address to send data. For instance, you may be
connecting to a World Wide Web server with the domain name "rs.internic.net",
but as far as the network is concerned, you are connecting to the Web server with the IP
address associated with that domain name.