Perplexity.ai is a leading AI-powered search engine in 2026, providing accurate, cited answers with real-time web access and multi-step reasoning. It features advanced models (GPT-4o, Claude 3.5, etc.), file analysis, image generation, Pro Search, Spaces, and Labs for reports/projects. Free tier with limits; Pro at $20/month for unlimited access—ideal for research, learning, and productivity.