Create simple nodejs server

Create file using vi editor

> vi app.js

> var http = require('http');

> http.createServer(function (req, res) {

> res.writeHead(200, {'Content-Type': 'text/plain'});

> res.end('Hello World\n');

> }).listen(80, '0.0.0.0');

Save and quit

> :wq

run app as super user to run on port 80

> sudo node app.js