JavaScript web library pattern

mylib.js

(function(){ // Wrap everything up in a function

var count,person; // These become private to this wrapped scope, and do not clutter the global namespace.

count=0; // Modify private count var,

person= function(name){
  this.name = name;
  count++;

  this.countPeople = function(){
    return count;
  }
}

window.Person = person; // Export my person and make it reachable through window.Person;

})(); // Execute the wrapped code