Icons are images which are used to represent files and folders in a computer system. On Ubuntu, most icons are stored in
Ubuntu often uses scalable icons in .svg format so that they can be used at any size. However, many icons in the system are still sized at various sizes in .png format. In addition, scalable icons may be made differently for different sizes.
Many media types have their own thumbnail icons which represent the file itself. For example, a music file might have an icon which shows the album artwork for that song.
Icons can be themed using third party utilities. This will change the common icons (e.g., folder icons, home folder, common applications, filetype icons) across the system.