Socket.IO enables real-time bidirectional event-based communication.
It works on every platform, browser or device, focusing equally on reliability and speed.
Real-time analytics
Push data to clients that gets represented as real-time counters, charts or logs.
Binary streaming
Starting in 1.0, it's possible to send any blob back and forth: image, audio, video.
Instant messaging and chat
Socket.IO's "Hello world" is a chat app in just a few lines of code.
Document collaboration
Allow users to concurrently edit a document and see each other's changes.
USED BY EVERYONE
From Microsoft Office, Yammer, Zendesk, Trello... to hackathon winners and little startups.
One of the most powerful JavaScript frameworks on GitHub, and most depended-upon npm module.