The document discusses real-time web APIs and protocols for pushing data from servers to web clients in real-time, including long-polling, PubSubHubbub, webhooks, websockets, and server-sent events. It also examines services like Pusher and Kaazing that provide these capabilities and promising approaches like using PubSubHubbub, server-sent events, or websockets with additional protocols to indicate media types and enable bi-directional communication.