What is a Domain Name?

    A domain name identifies its position in the global Internet. If you think of the Internet as a huge C: Drive, then a domain name is a unique Directory on that drive. A domain name, like a directory, can also have sub-directories. These are call sub-domains. Believe it or not, the "WWW"s you see in web-site addresses are really sub-domains of the domain name. Sub-domains were initially used to specify unique computers within a domain's network. However today, many sub-domains can reside on the same computer.
    Example: yahoo.com is a domain name. www.yahoo.com is a sub-domain of yahoo.com. Go to Yahoo and enter a word to search on. You'll notice the URL changes to begin with search.yahoo.com. Search is probably a specialized computer in the Yahoo network used just for searching.