It is just as important to understand how users will access your help as it is to identify your audience correctly.
If you are writing help for an application, you need to decide which topics are browsable and which topics are available from the application as context-sensitive help. A topic is browsable if you can navigate to it using the topic tree or hyperlinks. Topics designed exclusively for context-sensitive help might not be browsable because the only way to display the topic may be from within a particular context in the application.
You must also decide if you want your application's help volume to be registered. Registered help volumes can be displayed by other applications (such as the Help Viewer), making the information more widely accessible. If another help volume contains hyperlinks to topics in your help volume, your help volume must be registered.
See "Registering Your Application and Its Help" for information about installing and registering your application.
If you are writing a standalone help volume (a help volume not associated with an application), you may choose to do things differently.
First, you must provide a path for users to get to all the topics you've written. That is, every topic must be browsable through at least one hyperlink. Also, because there's no application associated with your help, you must rely on a help viewer (such as Help Viewer) to display your help volume.