A favicon short for favorite icon, also known as a shortcut icon, website icon,  is a file containing one or more small icons, associated with a particular website or web page.

A web designer can create such an icon and upload it to a website (or web page) by several means, and graphical web browsers will then make use of it. Browsers that provide favicon support typically display a page's favicon in the browser's address bar (sometimes in the history as well) and next to the page's name in a list of bookmarks. Browsers that support a tabbed document interface typically show a page's favicon next to the page's title on the tab, and site-specific browsers use the favicon as a desktop icon.

Selecting a favicon image, and setting it is very easy. Use the KickstartCassiopeia tab for the favicon. Enable loading of it and select your image. The recommended basic size for this icon is 152×152 pixels. For the iPad, the basic size is 180x180 pixels. Android tablets [via Chrome] prefer a 192x192 PNG icon. 

Set the colors for transparency if needed, and a tile color for Windows, and you are all set. Yes, KickstartCassiopeia has you covered!