In Windows–land, the Shell is the GUI. It’s Explorer putting icons and things on the screen. Those icons usually represent files and directories. Each icon can

In Windows–land, the Shell is the GUI. It’s Explorer putting icons and things on the screen. Those icons usually represent files and directories. Each icon can be different, usually determined by the file extension or by metadata inside the file. On top of those icons you can add overlays. TortoiseSVN adds overlays to indicate the state of files inside of an SVN repository. Dropbox likewise adds icons to files inside of a synced folder. They have to fight because Windows is dumb.