load & unload

load & unload

i can load pages using "load"  and is it poosbile to unload this pages (any command like unload) likewise css file



for example

  1.             $("#l5").bind('click',function(){
  2.                      $('#irtibat').load('contact.html');
how can i unload this page
  1. $("head").append("<link>"); var css = $("head").children(":last"); css.attr({ rel: "stylesheet", type: "text/css", href: "main.css" });
how can i unload this css file