Whats a Subdomain Good For?
With a subdomain, you can clearly indicate important subdivisions of your site, like departments, functions, or services. For example, universities might use subdomains for their major divisions, like humanities, social sciences, and physical sciences, like this: http://humanities.uchicago.edu/ An online seller might distinguish their company information from their forum from their webstore, from their affiliates program, like this: http://affiliate-program.amazon.com/ Subdomains can also designate individual host servers, and subdomains such as ftp and mail do this, in this way: http://mail.google.com/ Different server clusters can be specified as well, using discriminators such as www2, www3, etc. http://www6.comcast.net/ Note that it is possible to construct website divisions with paths that follow the domain name and which are divided by slashes, like this: http://www.uchicago.edu/admissions/ http://www.google.com/firefox Subdomains can also be used to allow separate site sections