PubNub is a programmable network for developing realtime applications; an evolution from three-tier architecture, purpose-built to handle all the complexities of data streams. PubNub operates at the edge of the network to handle and apply logic to real-time data, thereby minimizing latency to 250 milliseconds or less worldwide, and guaranteeing reliability and scalability.
Please read the How PubNub Works guide to get a solid understanding of what PubNub can do for your applications.