Domain name

This is the name that identifies an web site. For example, "apple.com" is the domain name of Apple Computer's web site. A single web server may have more than one domain name, but a single domain name points to only one machine. To use Apple Computer as an example again, www.apple.com, support.apple.com, and store.apple.com could be served on one to three machines. It is also possible, and quite common, for a domain name to be registered, but not be connected to an actual machine. The reason for this is usually so that a company or group can have e-mail addresses at a certain domain without having to maintain a web site. In these cases, there still must be a machine to handle the mail of the listed domain name.

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