Raise your hand if you've ever doodled mindlessly in a notebook.
It turns out that you doodlers are in good company, and that people in medieval times couldn't resist drawing in the blank spaces in their books either.
English professor Erik Kwakkel has encountered dozens of incredible margin doodles in the course of his work, and has begun to share them on his blog.
Kwakkel is an English professor at the University of Leiden in the Netherlands, and focuses on medieval manuscripts.