The Unused Index Entries report tracks all the entries in your index that are not associated with any topics. Use it to:
Identify index entries that you can remove from your project
Find keywords that need to be associated with topics
Review cross-references included in your index
Tip: If you no longer need any of the keywords listed in the report, you can quickly remove all of them to "clean up" your index. For details, see Removing unused keywords.