The Pocket Guide to the Popes
This book contains the abridged profiles of all of the popes of the Catholic Church organized chronologically according to the dates of their respective terms of office.It consists of  quick thumbnail sketches of each pope, one to three paragraphs detailing who they are, their history, the important events of their papacy, and their overall place in the history of the time.
For anyone who's just looking for a quick few facts on the popes.