This attribute determines the character font index used when
drawing each element of graphical output produced by a PlotPlot. It
takes a separate value for each graphical element so that, for
instance, the setting "Font(title)=2" causes the Plot title to
be drawn using font number 2.
The range of integer font indices available and the appearance
of the resulting text is determined by the underlying graphics
system. The default behaviour is for all graphical elements to
be drawn using the default font supplied by this graphics
system.