A favicon (short for favorites icon and pronounced fav-eye-kon) is a 16x16 image. A favicon generally has an .ico extension. .Gif extensions can also be used as a favicon but is not recommended unless you have an animated image. In most browsers, the favicon is placed by the URL of a website in the address bar and by the Site Name of the website in the favorites/bookmarks. It is used alongside a logo to help distinguish between websites.

Favicons, back in the days of yore, were made by using programs such as Visual Basic. To meet the demand of custom favicons, and thanks to the high price of Microsoft Visual Basic, programs came out that exclusively created and edited the 16x16 .ico image. New advances to PHP however, enabled a “Favicon Generator” which converts all images to the .ico extension. Now making a favicon is easier than ever. You may use your favorite picture editor (i.e. Adobe Photoshop) to create a 16x16 image.
You can also use a image of any size and it will be automatically resized. Then, use the Favicon Generator to convert the image to a favicon with a .ico extension.

Installing a favicon on your website is easy. Simply upload the image
(favicon.ico) into your public_html, or wherever your website files are located. Then put this code into your pages:
<link rel="shortcut icon" href="/favicon.ico" />

FaviconExpert and Favicon.com offers professional favicon services.
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