帮帮忙看看这段代码谢谢了

mainWin=window.open("sys/WebUserCustom.aspx?act=Redirect","MainWindow", "fullscreen=no,toolbar=no, menubar=no, scrollbars=yes,resizable=yes,location=no, status=no, top=0, left=0, height=" + screen.availHeight + ", width=" + window.screen.availWidth);能不能帮我具体解释一下谢谢了！