icon in header html code example
Example 1: add icon website
<link rel="icon" href="http://example.com/favicon.png">
Example 2: how to change tab icon in html
<link rel="shortcut icon" href="http://sstatic.net/stackoverflow/img/favicon.ico">
<link rel="icon" href="http://example.com/favicon.png">
<link rel="shortcut icon" href="http://sstatic.net/stackoverflow/img/favicon.ico">