NotebookLM

NotebookLM works differently from a general chatbot: you upload your own sources — PDFs, Google Docs, slides, websites, or pasted text — and the AI answers questions, summarizes, and generates study guides using only that material, with inline citations back to the specific source passages. This source-grounding significantly reduces hallucination risk for research, study, and document-review tasks compared to general-purpose assistants. A standout feature is "Audio Overview," which turns your uploaded sources into a podcast-style discussion between two AI hosts. The free tier covers a generous number of notebooks and sources for individual use; NotebookLM Plus, bundled into the Google One AI Premium plan (around $19.99/mo), raises source and notebook limits and adds team-sharing features. Its main limitation is that it won't answer general questions outside your uploaded sources — for that, you'd use Gemini directly.