NotebookLM is Google's AI note-taking tool that works only with the sources you give it. You upload PDFs, paste web links, or add text, and then ask questions. The answers are grounded in your documents, with citations pointing back to the specific passages. This makes it different from general chatbots that may pull from unverified web content. You can also generate mind maps, quizzes, and summaries from your sources.

It's useful for researchers dealing with a pile of papers, students working through readings, or anyone trying to extract answers from a long document without reading every page. The interface shows your sources on the left and the chat in the middle, so you can verify claims as you go. It's free to use with a Google account.