A ComponentOne Doc-To-Help 2007 project file is a database that stores information about a Help project. Doc-To-Help maintains everything except the actual content of the source documents in a project file. Specifically, Doc-To-Help project files contain the following elements:
Source document paths
Document template paths
Topic titles derived during compilation
Paragraph style behaviors
Character style behaviors
Script code modules
Help window definitions
Index keywords visible to the reader
Group names hidden from the reader
The icons shown here are used throughout Doc-To-Help to identify elements of a specific type and to indicate relationships between disparate elements.
Since a Doc-To-Help project file is a database, it must exist on your hard disk or a network drive; it cannot reside in memory like a new document in Microsoft Word or FrontPage. By default, Doc-To-Help project files have a .d2h extension.
More:
Changing the Current Help Target
Building the Current Help Target
Viewing the Current Help Target