(function($){
    $.fn.ChangeStyle = function(options,msg){var opts = $.extend({},$.fn.ChangeStyle.defaults, options); this.css("background",opts.background);  
            this.css("color",opts.color); //private method
            Note(msg);//public method
            $.fn.ChangeStyle.customAction();
                    };function Note(msg)
    {if(undefined != msg)
        {
            alert(msg);
        }
    }
    $.fn.ChangeStyle.defaults = { background:"#999",color:"red"};
        $.fn.ChangeStyle.customAction = function(){};
})(jQuery);
 //Invoke the pluign example
$(function()
{
 //set properties
 //$("form").ChangeStyle.defaults.background = "#f1f1f1";
 //$("form").ChangeStyle.defaults.color = "blue";
 $("form").ChangeStyle.customAction = function(){ alert("this is custom action")};
 $("form").ChangeStyle({ background:"#999",color:"red"},"hi");
});