A site is a collection of publicly available, woven Websites that share a single domain. Sites can be produced and preserved by a private, group, business or company to offer a selection of objectives. Together, all publicly available websites make up the Internet. Sites are available in a nearly limitless selection, including educational websites, information websites, discussion forums, social networks websites, ecommerce sites, and more.
What is Pligg?

Pligg is an open source content management system that lets you easily create your own user-powered website.