The "system tray" or notification area is normally used for transient icons that indicate some special state. For example, a system tray icon might appear to tell the user that they have new mail, or have an incoming instant message, or something along those lines. The basic idea is that creating an icon in the notification area is less annoying than popping up a dialog. Aobject can be used to display an icon in a "system tray". The icon can have a tooltip, and the user can interact with it by activating it or popping up a context menu. Critical information should not solely be displayed in a , since it may not be visible (e.g. when the user doesn't have a notification area on his panel). This can be checked with gtk_status_icon_is_embedded(). On X11, the implementation follows the freedesktop.org "System Tray" <ulink url="http://www.freedesktop.org/wiki/Specifications/systemtray-spec">specification</ulink>. Implementations of the "tray" side of this specification can be found e.g. in the GNOME 2 and KDE panel applications. Note that a GtkStatusIcon is <emphasis>not</emphasis> a widget, but just a . Making it a widget would be impractical, since the system tray on Win32 doesn't allow to embed arbitrary widgets.