There are logs that allow you to keep track of all of the crunch and data that is a Player Character. This is not one of those logs.
The Master Player's Adventurers Journal is an "In Character" record book designed to allow your character's to tell their story from adventure to adventure. Each page in the Journal, from Session Start to Conclusion and Final Thoughts allow them to chronicle, map, log, and otherwise tell THEIR story. Let them capture information about enemies and allies that may be useful in future adventures, and much more!