NotebookLM is Google's AI-powered research and note-taking tool that lets you upload your own documents and have a grounded, source-cited AI conversation with them — turning any collection of sources into an interactive, intelligent knowledge base.

Perplexity AI is an AI-powered search engine that answers questions directly with cited, real-time web sources — combining the speed of traditional search with the synthesis power of large language models to replace hours of research with seconds of insight.