网页导航条。导航栏是指位于页面顶部或者侧边区域的，在页眉横幅图片上边或下边的一排水平导航按钮，它起着链接站点或者软件内的各个页面的作用(The navigation bar is located on the top of the page or the side of the region, in a row of horizontal navigation button header above or below the banner images, it plays a link to t