Portlet

Portlets are pluggable user interface software components that are managed and displayed in a web or enterprise portal.

Portlets produce fragments of markup (HTML, XHTML, WML) code that are aggregated into a portal. Typically, following the desktop metaphor, a portal page is displayed as a collection of non-overlapping portlet windows, where each portlet window displays a portlet. Hence a portlet (or collection of portlets) resembles a web-based application that is hosted in a portal.

Some examples of portlet applications are e-mail, weather reports, discussion forums, and news.

Portlet standards are intended to enable software developers to create portlets that can be plugged into any portal supporting the standards.

Portlet-based solutions are an example of component-based software engineering.

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