The Lists function will allow you to extract from your result a selection of relevant documents. This permanently stored selection is a custom hitlist that can be used or acted on later, for instance to display or export documents, download PDFs, add it to a workfile, analyse it, and even integrate it as a script in a search strategy.
The lists are updated automatically; once a new equivalent, for example, is added to the family. That family will be updated in the list. That update is made once you open the list.