<meta>标签,<meta>有指定name和指定http-equiv两种用法,<meta name="名字" content="值" />,<meta http-equiv="名字" content="值" />两种用法。
<meta http-equiv="Content-Type" content="text/html;charset=utf-8" />指定网页编码
<meta http-equiv="Refresh" content="3" />三秒后刷新此网页
<meta http-equiv="Refresh" content="3";url="http://www.baidu.com" />
<meta http-equiv="Cache-Control" content="no-cache" />禁止浏览器缓存页面