var foo = "foo";

(function(){ // Can be named or anonymous
	var foo= "bar";
	console.log(foo); // bar
})()

console.log(foo) // "foo"


//Ex 2
var foo = "foo";

(function(bar){ // Can be named or anonymous
	var foo= bar;
	console.log(foo); // foo
})(foo)

console.log(foo) // "foo"