Pro. Part of Reading Vault Pro.
This is where your reading meets the rest of your vault. Link a highlight to a Topic note, and the passage becomes part of what you know about that subject, right next to your other notes.
A Topic note is a regular note about one subject, like “Stoicism” or “Habits”. Reading Vault keeps them in your Topics folder.

Reading Vault adds a real Obsidian link from the highlight’s note to the Topic note. That means it shows up in the Topic note’s backlinks and in your graph.
With a book open, the Highlights tab lists that book’s highlights. With no book open, it lists highlights from your whole library, each with a small cover so you know where it came from.