Portal Vs Portlet

A portal page is made of a set of portlets. For example, the portal page such as Welcome contains portlets such as Navigation, Language, and so on And the portlet Language has icons (such as Look and Feel, Configuration, Minimize, Maximize, and Remove), title icon and title (such as Language), and a window which may contain contents (such as a set of language icons and links).

In a normal way, a portlet is an application that provides some content (such as information or service) that forms part of a portal page. A portlet container handles the portlets. A portlet container also processes requests and generates dynamic content. Actually, portals use portlets as pluggable user interface to provide a presentation layer information.

It's like the difference between a Servlet and an application server.

A portlet is an interactive component that delivers content to the end user. Developers develop portlets, just like developers develop Servlets.

A portal server runs portlets, and delivers a portal page to the end user. A portal page can potentially be an aggregation of many, many individual portlets.

Web Portal :

A web portal is a web-based platform that provides employees, customers and suppliers with a single access point to information. A web portal can be used to provide the user with personalised information such as employee training, safety manuals or a customer profile.

Portal Server Vs Application Server :

An Application Server provides a Servlet and JSP engine, not to mention a potential EJB container.

A portal server extends the application server by providing a container that can run Portlets, which currently are at the JSR168 standard .