HelpScribble 

HelpScribble is a full-featured, easy-to-use help authoring tool for creating help files from start to finish. You can create WinHelp (.hlp) files, HTML Help (.chm) files, a printed manual and online documentation (on a web site) all from the same HelpScribble project.

You can use the help files you make with the program to provide context-sensitive help with your Windows applications, no matter which development tool you use. You can also use HelpScribble to create stand-alone portable documents.