Favicon is the small icon that appears in the left of the url of a website up in the browser. It stands for favorites icon and is thought to be used to identify your website.
Favicon is a small 16×16 px icon named favicon.ico
How do you create a favicon? The easiest way to create one is use online services. I personally use the one here http://tools.dynamicdrive.com/favicon/. You need simply to upload the image in the upload field and you’ll have your favicon ready in seconds.
Upload your new favicon.ico file inside the theme folder and in the header.php file, inside the <head> </head> tags add this line of code :
<link rel=”shortcut icon” href=”<?php bloginfo(‘template_directory’); ?>/favicon.ico” />
Your favicon will appear in the browser in seconds.