"causes the Plot border to be drawn using line style 2 (which might result in, say, a dashed line).
The range of integer line styles available and their appearance is determined by the underlying graphics system. The default behaviour is for all graphical elements to be drawn using the default line style supplied by this graphics system (normally, this is likely to give a solid line).
For a list of the graphical elements available, see the description of the Plot class.
If no graphical element is specified, (e.g.
" instead of
" ), then a
operation will affect the attribute value of all graphical elements, while a
will use just the Style(Border) value.