A favicon is an icon associated with a particular Web page and/or Web site.
Favicons are small square images usually 16×16 pixels
You have probably seen many favicons before, even if you don't know what they are
A favicon (/ˈfæv. ɪˌkɒn/; short for favorite icon), also known as a shortcut icon
Favicon is a file containing one or more small icons / usually 16×16 pixels /
which are used by web browsers to show a graphical representation of the site
1. You can design a favicon image using an editor Photoshop or GIMP. Convert the Image to format ico and upload it to your website via ftp.
2. Find online favicon generator. Download it and upload to your website.