Character Dayplanners are an in-character version of the regular dayplanner.

Characters can describe their day as if they were making notes in a journal or what have you. It should have links to threads and also include off-panel activities, such as meals, training, reading or whatever you've not actually played out.

Or it can just be a list of links, but it should also include off-panel activities as above.

This is the place that other players come to see where your character has been and what they've been up to. It's especially useful for new players to get a gauge and catch-up if someone doesn't have time to read a full thread. There should be a separate thread for each of your characters.

Regular Dayplanners are designed to help you in planning your character's day before/while it happens. It can have links or just notes and is there solely to aid you as a player.