浏览器
shell 内核
Google Chrome Webkit/blink
Fire Fox Gecko
Safair Webkit
Opera presto
IE trident
主体结构
html标签
head标签
body标签
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title></title>
</head>
<body>
</body>
</html>
