If you are researching the evolution of the romance genre, digital archives are useful. A historical archive of romance shows how themes of love have changed over the decades. I often download PDF versions of older books to compare them with modern novels and see how the tropes have shifted...
I have always been a fan of collecting rare and hard-to-find stories. An online archive of romance often holds titles that are unavailable in local bookstores. Getting these in PDF format is a great way to preserve literary history while enjoying a touching story of love and relationships...