Web Configuration - Concepts
Sites
A unique site can be created for a specific customer base. A service provider can create a site per customer.
For example:
an educational organization may want different sites for staff and students.
A company can create two different sites - an internal site for employees, and an external site for customers.
Multiple sites can be added in a single property set. Sites are property set dependent. They can be shared within a specific property set, but will not work when imported into another property set. The web definitions linked to a site, however, can be shared across property sets.