A sub-domain is an individual and separate web folder that can be created and attached to the main domain. This sub-domain can have its own FTP password. It can also have its own private CGI-Bin folders, and all other characteristics of an individual domain. But this sub-domain need not be registered as a separate domain and this means that the affiliate need not spend additional money for the setting up of the sub-domain.

How can a sub-domain help an entrepreneur achieve success in his affiliate marketing business? A sub-domain can help the affiliate in two ways. These are optimization in search engines and diversification of the affiliate