Domain Name Systems

ALSO CALLED: DNS
DEFINITION: A domain name locates an organization or other entity on the Internet. For example, the domain namewww.totalbaseball.comlocates an Internet address for "totalbaseball.com" at Internet point 199.0.0.2 and a particular host server named "www". The "com" part of the domain name reflects the purpose of the organization or entity (in this example, "commercial") and is called the top-level domain name.  … 
Definition continues below.

DOMAIN NAME SYSTEMS DEFINITION (continued): …  The "totalbaseball" part of the domain name defines the organization or entity and together with the top-level is called the second-level domain name. The second-level domain name maps to and can be thought of as the "readable" version of the Internet address.A third level can be defined to identify a particular host server at the Internet address. In our example, "www" is the name of the server that handles Internet requests. (A second server might be called "www2".) A third level of domain name is not required. For example, the fully-qualified domain name could have been "totalbaseball.com" … 
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