Node.js

Original author(s)	Ryan Lienhart Dahl
Developer(s)	Node.js Developers
Stable release	0.6.14 / March 22, 2012; 15 days ago (2012-03-22)
Preview release	0.7.7 / March 30, 2012; 7 days ago (2012-03-30)
Development status	Active
Written in	C++, JavaScript
Operating system	Mac OS X, Linux, Solaris, FreeBSD, OpenBSD, Windows (older versions require Cygwin), webOS
Type	Event-driven networking
License	MIT License
Website	nodejs.org

Node.js is a software system designed for writing scalable internet applications, notably web servers.^[1] Programs are written in JavaScript, using event-driven, asynchronous I/O to minimize overhead and maximize scalability.^[2] Node.js consists of Google's V8 JavaScript engine plus several built-in libraries.

Node.js was created by Ryan Dahl starting in 2009, and its growth is sponsored by Joyent, his employer.^[3][4]

Similar environments written in other programming languages include Twisted for Python, Perl Object Environment for Perl, libevent for C and EventMachine for Ruby. Unlike most JavaScript programs, it is not executed in a web browser, but is instead a server-side JavaScript application. Node.js implements some CommonJS specifications.^[5] It provides a REPL environment for interactive testing.

Node.js was selected by InfoWorld for the "Technology of the Year Award" in 2012.^[6]

Examples

This is a complete implementation of hello world as an HTTP Server in Node.js:

var http = require('http');
 
http.createServer(function (request, response) {
    response.writeHead(200, {'Content-Type': 'text/plain'});
    response.end('Hello World\n');
}).listen(8000);
 
console.log('Server running at http://localhost:8000/');

The following code is a simple TCP server which listens on port 7000 and echoes 'hello' upon connection:

var net = require('net');
 
net.createServer(function (stream) {
    stream.write('hello\r\n');
 
    stream.on('end', function () {
        stream.end('goodbye\r\n');
    });
 
    stream.pipe(stream);
}).listen(7000);

Community

Node.js has a developer community primarily centered on two mailing lists, nodejs and nodejs-dev, and the IRC channel #node.js on freenode. The community gathers at NodeConf, an annual developer conference focused on Node.js.^[7]

See also

Free software portal

• NPM, the Node Package Manager - the predominant package manager for Node.js. As of Node.js version 0.6.3, npm is installed automatically with Node.js.
• JSAN, the JavaScript Archive Network - a lesser used JavaScript package manager.
• Opa, an alternative approach to writing web apps, sharing many characteristics of Node.js

References

External links

• Official website
• The Node.js Package Manager
• Ryan Dahl: Node.js | JSConf.eu on Blip