I was wondering sometimes, the first result in Google's results has a list of pages (in the website) below the title of the search result.
Is this something I can force Google to do, with some sort of HTML tags?
Or does Google just do it automatically, when it feels like it?
I think you may refer to sitelinks. They are automatically generated by Google.
We only show sitelinks for results when we think they'll be useful to the user. If the structure of your site doesn't allow our algorithms to find good sitelinks, or we don't think that the sitelinks for your site are relevant for the user's query, we won't show them.
At the moment, sitelinks are automated. We're always working to improve our sitelinks algorithms, and we may incorporate webmaster input in the future. There are best practices you can follow, however, to improve the quality of your sitelinks. For example, for your site's internal links, make sure you use anchor text and alt text that's informative, compact, and avoids repetition.
