In Burp Suite Enterprise Edition, the "Sites" page contains a list of sites that you have configured, which each represent a website or web application that you want to scan and track. Sites can be organized into a hierarchical tree structure using folders. You can set up the site tree however you want. For example, you might choose to group websites based on their geographical location or based on the different teams of developers that work on them. You can also restrict user access to certain parts of the site tree based on this folder structure.
Once you've run a few scans, the "Sites" page will also provide an overview of how many issues need your attention in each site or folder. The filter bar lets you show or hide items based on particular features. For example, you can choose to only show sites for which there are problems that need your attention.
Hovering the mouse over a site shows contextual options, such as creating a new scan for the site.
You can click on a site to see more site details.