Perplexity AI is an AI-powered answer engine that combines real-time web search with large language model reasoning to provide accurate, cited, up-to-date answers to any question. Unlike ChatGPT's static training data, Perplexity grounds every answer in current web sources with inline citations — dramatically reducing hallucinations and enabling responses about today's events and data. Over 15 million users including researchers, students, professionals, and curious minds use Perplexity as their default search alternative, finding it more reliable and efficient than traditional search engines for getting to definitive answers.