Mac OS Help
http://developer.apple.com/macos/help.html

Apple Inc.

Abstract:

Online help facilities are an important part of any software product in today's marketplace. Apple has a number of technologies specifically designed for providing both convenient to use and easy to understand online help. Interested developers can take advantage of these technologies and use them to build online help facilities into their own products. This page provides an overview of the current Apple help technologies along with links to other related resources.