I know that a list of posts is generated automatically in WordPress, but what I have been looking for is to have a summary of pages, possibly in a hierarchic format, that resides at the side of a certain page. Here is an example: http://www.w3schools.com/js/js_variables.asp
That website does not use Wordpress though, but that's the kind of functionality I am looking for. I know how to assign a parent page when creating a new page, but I don't know how to generate a summary and put it on the side. Do I need any specific plugin for this?