file.nb is a Mathematica notebook file.
$FrontEnd is a global variable that specifies to what front end object, if any, the kernel is currently connected.
ReleaseGUIObject[obj] closes and terminates all resources of a live GUIObject instance.
DefaultNewCellStyle is a notebook option which specifies the default style to use for new cells created in the notebook.
LocalizeVariables is an option to Manipulate that determines whether the values of variables associated with controls should be localized.
UsingFrontEnd[expr] evaluates expr, making use of a front end if necessary.
Mathematica allows convenient discovery and customization of all aspects of its system setup.
CloseGUIObject[interface] closes a live GUIObject instance.CloseGUIObject[] requests that an interface close, when called within a Script block.
CellEventActions is an option for Cell that gives a list of actions to perform when specified events occur in connection with a cell in a notebook.