Java based help system

 The JavaHelp system is an online help system that developers can use to add
 online help to their Java platform applications. The JavaHelp system provides
 developers and authors with a standard, fully featured, easy to use system for
 presenting online information to Java application users. The JavaHelp system
 consists of a fully featured, extensible specification and API, and
 a reference implementation of that specification and API that is written
 entirely in the Java programming language. The JavaHelp system reference
 implementation, based on the Java Foundation Classes (JFC, also known
 as Swing), provides a standard interface that enables both application
 developers and authors to add online help to their applications.