Mathematica provides standardized special characters to represent various forms commonly used to annotate or structure text.

StochasticMomentumIndex

Copy Graphics Selection copies the selected (or clicked upon) object within the graphic to the clipboard.

Input from Above copies and pastes contents of the nearest preceding input cell.

X Environment Information opens a dialog box that displays the current attributes of the X front end environment (X only).

ActiveStyle is an option for Hyperlink and related constructs that specifies styles to add when the constructs are active, typically as a result of the mouse being over them.

AlphaChannel[image] returns the alpha channel of image.

Beep[] generates an audible beep when evaluated.

CellDynamicExpression is an option for cells that specifies an expression to be dynamically updated whenever the cell is visible on-screen.

CellEpilog is an option for Cell which gives an expression to evaluate after each ordinary evaluation of the contents of the cell.