The update means Google's Gemini 1.5 Pro-powered virtual assistant can now handle Google Docs, PDFs, text files, Google Slides, YouTube video URLs, audio files and web pages. This expands NotebookLM's potential sources to include lecture recordings, informative YouTube content and group discussions. Google claims that it securely stores all information uploaded to NoteBookLM and does not use it to train AI. Google launched the virtual research assistant in the summer of 2023 and upgraded it to run on Gemini 1.5 Pro this past June. Alongside the AI-powered bump, Google expanded NotebookLM to be available in over 200 countries and territories.