For about thirty years, writing in books was treated as something between a minor crime and a personality flaw. Used bookstores marked annotated copies down. Librarians shook their heads. The cleanest copy was the most valued copy. Then, sometime around 2021, the entire convention reversed itself.
Open a popular BookTok video today and the page is unrecognizable from a 2010 paperback. Five colors of tab. Marginalia in pencil. Underlining in two weights. Sticky notes folded into the spine. The reader has done to the book what a textile artist does to a quilt: made it visibly hers.
A vocabulary of tabs
There is now a roughly shared annotation system across the community. The colors are not standardized, but the categories are. Different tabs mark dialogue worth rereading, sentences the reader wants to remember, scenes that made them cry, scenes the algorithm calls spicy, and foreshadowing they want to come back to on the reread. Most serious readers can decode another reader's tab system inside about ten seconds.
This is not decoration. It is an interface. The annotated book is a personalized index into the book's most important moments. On reread, and most of these books are reread three or four times, the tabs are the entry point.
“Annotation is the reader insisting that the book happened to them, not just in front of them.”
What annotation is actually doing
A subtler thing is happening here, too. To annotate a book is to slow down. The hand has to move. The pen has to find a margin. The decision to mark a line forces a small pause in the reading flow, and that pause is when the line lands. Readers who annotate consistently report higher long-term retention of what they read, and the research literature on active reading agrees with them.
Annotation is, in this sense, a defense against the speed at which we now consume everything else. It is a deliberate friction. It says: this passage is worth interrupting myself for.
The book as a personal object
There is a generational shift underneath all of this. A reader who grew up with ebooks and library holds did not have a personal relationship with the physical artifact of a book. The artifact was interchangeable. The text was what mattered. Buying a paperback specifically to annotate it is the reversal of that: an insistence that the artifact is part of the experience, not a substrate for it.
It is the same impulse driving vinyl, film photography, and handwritten letters. The artifact is the point. The annotated book is just the literary version.