Rare, wonderful item. (Requires attention from someone who is able to read and write).
Usually, this magical book copies are written and also drawn the information in the attuned user’s handwriting and the style. You or another creature can place a piece of paper or paper like the material inside this book, and then close it. Any pages within the contact with the information are written or drawn by the attuned user in handwriting or in the drawing style. Copying information onto a page that is already used will erase the old information.
It is holding and attuned with this book. You can use the bonus action to think about the document that has been copied into the book.
Imagine that a book could become attuned with a new creature or that it loses its connection to the creature. Then all pages will blink.
The book of Memory usually has 100+ pages 10d10, with each page having two sides.