Non-blocking vs blocking example

blocking.js

var fs = require('fs')​;

fs.writeFileSync('message.txt', 'Hello Node.js');
console.log('This will not print until the file is saved. Sync means do not use non-blocking.');

non-blocking.js

var fs = require('fs')​;

fs.writeFile('message.txt', 'Hello Node.js', function (err) {
  console.log('File is saved!');
});
console.log('This will fire before the file is saved because on non-blocking io');