What is a JWindow ???

A JWindow is a container that can be displayed anywhere on the user's desktop. It does not have the title bar, window-management buttons, or other trimmings associated with a JFrame, but it is still a "first-class citizen" of the user's desktop, and can exist anywhere on it.
(Description From Java API)

JWindow also suitable when we want to build a splash screen for an application. What is splash screen ???
-Splash screen is a term used to describe an image that appears while computer program is loading(FROM WIKIPEDIA).
-For example :
Splash screen for Microsoft Word 2003