Tornado Web Server

Tornado is a Python web framework and asynchronous networking library that provides non-blocking I/O, making it ideal for applications requiring long-lived connections such as WebSockets, long polling, and streaming. Originally developed by Bret Taylor at FriendFeed in 2009 and open-sourced after Facebook acquired FriendFeed, Tornado is maintained by the Tornado authors and community. Key features include: asynchronous I/O (non-blocking event loop based on epoll or kqueue, enabling thousands of concurrent connections per process), coroutine support (native Python async and await syntax with tornado.gen for backward compatibility, enabling clean asynchronous code), WebSocket support (built-in WebSocketHandler for bidirectional real-time communication), HTTP server and client (high-performance non-blocking HTTP server suitable for production deployment behind a reverse proxy), templating engine (Tornado templates with auto-escaping, expression evaluation, block inheritance, and UI modules for reusable components), authentication (secure cookie-based authentication, OAuth2, OpenID, and third-party integration), routing (URLSpec routing with named captures and host-based routing), non-blocking database (asynchronous drivers for PostgreSQL, MySQL, MongoDB, and Redis via motor and aiomysql), static file serving (built-in static file handler with caching headers), and scalability (used by Pinterest, Quora, and Facebook for real-time features handling millions of connections).