Introducing Socket.IO
The aim of Socket.IO is to make real-time apps possible in every browser and mobile device. It supports several transport protocols, choosing the best one for the specific browser.
If you were to implement your application with WebSockets, it would be limited to the modern browsers supporting that protocol. Because Socket.IO falls back on so many alternate protocols (WebSockets, Flash, XHR, and JSONP), it supports a wide range of web browsers, including some old crufty browsers.
As the application author, you don't have to worry about the specific protocol Socket.IO uses in a given browser. Instead, you can implement the business logic and the library takes care of the details for you.
Socket.IO requires that a client library make its way into the browser. That library is provided, and is easy to instantiate. You'll be writing code on both the browser side and server side using similar Socket.IO APIs at each end.
The model that Socket.IO provides is similar to the EventEmitter...
