I would like to have information about the icons which are displayed alongside the site URLs on a web browser. Is this some browser specific feature? Where do we specify the icon source, ie, is it in some tag on the web page itself ?
These icons are called favicons
Most web browsers support http://mysite.com/favicon.ico but the proper way to do it is to include an icon meta tag in the head profile.
<head profile="http://www.w3.org/2005/10/profile">
<link rel="icon"
type="image/png"
href="/somewhere/myicon.png" />
[…]
</head>
Your best bet is to probably do both with the same icon image.