Shortcuts are typically implemented as a small file containing a target URI or GUID to an "object", or the name of a target program file that the shortcut represents. The shortcut might additionally specify parameters to be passed to the target program when it is run. Each shortcut can have its own icon. Shortcuts are very commonly placed on a desktop, in an application launcher panel such as the Microsoft Windows Start menu, or in the main menu of a desktop environment. The functional equivalent in the Macintosh operating system is called an alias, and a symbolic link (or symlink) in UNIX-like systems.