The collections framework can take any messy and arbitrary tree data sctructure, like a JSON payload or HTML page, and convert it into a hierarchal set of collections.
Let's say we get a sample response from an API that looks like this, for restaurants and menu items:
The collections framework will build 2 collections, one for the parent-level restaurants and another for the nested menu items. You'll be able to download each collection separately, either in JSON or CSV format.