Navigation concept

A navigation likes a menu that helps users visualize the structure of a site and provides hyper links to quickly move from page to page. There is a bar which contains navigations called a Navigation bar. There are three navigation types:

• Navigation of Portal: This navigation type is used to keep the links to pages of Portal. Each portal has only one navigation and it is automatically created when a portal is created.
  
• Navigation of Group: All registered users are organized in groups. There is a navigation keeping the links to all pages of each group, called group navigation.
  
• Navigation of User: Each user has own navigation that keeps the links to pages. User's navigation is created automatically like Navigation of Portal when user is created (registered). This navigation only can be deleted when the user is deleted.