gistfile1.js

1. scope variable accesibility

...

var color = 'green';

var fun = function() { alert(color) }

..


fun() // alert('green')

// variables that are accesible 
// in the scope in which a function
// is defined are accesible within
// that function once called



2. trick to bind variable into the function

var fun = function(color) {
  return function() { alert(color) }
}('green')


fun() // alert('green')