Perplexity AI is an AI-powered search engine and answer engine that combines large language models with real-time web search to deliver accurate, citation-backed answers. Unlike traditional search engines that return a list of links, Perplexity synthesizes information from multiple sources and presents concise, well-structured responses with inline citations. It supports multi-step research mode for deep investigation, file uploads for document analysis, image generation, and video generation. Perplexity provides access to multiple frontier AI models including GPT-5.2, Claude Sonnet 4.5, and Gemini 3 Pro, allowing users to choose the best model for their query. The platform serves individuals, teams, and enterprises with a range of plans from free to enterprise-grade solutions.