<!Doctype html>
<html>
<head>
<meta charset="utf-8" />
<title>testing code</title>
</head>
<body>
<div style="float: left; width: 200px; height: 150px;
background-color: red;"></div>
<div style="background-color: gray;">
<div style="clear: left;"></div>
</div>
</body>
</html>
Can anyone explain why the heights of the red block and gray block are the same?