While homepages are the location where documents of a given doctype are stored, index pages provide additional views to these documents.

Typically an index page simply lists all documents of a given type alpha-numerically. In cases where the amount of documents increases, one such index will cease to be an effective tool to support browsing a documentation. In this case different index pages need to be created.

Index pages are provided by Confluence as part of page blueprints.

Confluence creates an index page and adds a shortcut to your sidebar (if you're using the default theme). The index displays a list of pages made with the blueprint, and information selected information from your blueprint pages.

Atlassian Documentation. Blueprints - Create content using a blueprint