JBoss Portal is made up of portals, portal containers, portal pages, and portlets. What are these things? Here are some definitions:
- Portal: Hosts the presentation layer for personalization, single sign on and content aggregation.
- Portlet Container: A Portal can host multiple portlet containers and each portlet container has its own runtime environment.
- Portal Page: Aggregation of portlets, organized and displayed on a single page.
- Portlet: A portlet is a Java technology based web component, managed by a portlet container, that processes requests and generates dynamic content.
- Portlet Instance: A portlet instance can be placed on multiple pages and will show the same state.
 |
Figure 3. Portal Definition Diagram.
Now let's look at that default portal page again with these terms in mind (Figure 4).
 |
Figure 4. The default portal page with components highlighted.
Now we see that the default portal we are looking at has three portal pages, and the default portal page has five portlets on it (navigation, greetings, user, portal pages, and content view). In addition, we see that each portlet window is made up of decorations/controls and a portlet fragment (navigation does not need decoration/controls). Each portlet can represent some fragment of information that you want to present to users. By having multiple portlets on a portal page, we can aggregate portlet information.