Here there is an invisible space between the
and
, interpreted as multiplication.
In the buttons in a palette, you often want to set up a template with placeholders to indicate where expressions should be inserted.
\[SelectionPlaceholder] marks the position where an expression that is currently selected should be inserted when the contents of the button are pasted.
\[Placeholder] marks other positions where subsequent expressions can be inserted. The
Tab key will take you from one such position to the next.
In describing how to enter input into
Mathematica, it is sometimes useful to give explicit representations for keys you should press. You can do this using characters like
and
. Note that
and
are actually treated as spacing characters by
Mathematica.
The fonts that are distributed with
Mathematica contain their own renderings of many ordinary keyboard characters. The reason for this is that standard system fonts often do not contain appropriate renderings. For example,
and
are often drawn small and above the centerline, while for clarity in
Mathematica they must be drawn larger and centered on the centerline.
