Index keywords are a list of words associated with a topic that are used to generate the keyword indexes in the output formats that support them. Keywords are entered and viewed in the Keywords: field of each topic's tab. In addition to this you can also view and manage the resulting index interactively by right-clicking in the Index tab in the Table of Contents / Index pane.
•See Keywords and Indexes for details on using these features.
Keywords can have sub-keywords, which are also described as child keywords. This is a standard feature of all indexes in both printed and electronic form. For example, an entry called Indexes might have the following kind of child keywords:
editing, in teams
Indexes cannot have more than one level of sub-keywords. This is a restriction of the output formats, not of Help+Manual. All the supported output formats only have one level of sub-keywords and Help+Manual is thus also limited to one level.
Producing a good index is not a process that can be automated. It is an art, not a science, and needs to be done manually. There is simply no alternative to the selection of individual relevant keywords in each topic by the author. For example, an index including all occurrences of all the words in your help would be worse than useless, because it would make it impossible to find anything relevant. You need to examine each topic individually and make individual decisions whether a word merits being added to the index or not.
It may be relevant to list every single reference to an author's name, for the sake of completeness. However, in a help file you will not want to list every single reference to most subjects. For example, index entries that refer to passing mentions in introductory chapters will simply waste the user's time. When users click on an index entry they want to find information that they can use, and that should be the criterion for including a term in the index.