SampledSoundList[{a_1, a_2, ...}, r] is a sound primitive that represents a sound whose amplitude has levels a_i sampled r times a second.
Scan
(Built-in Mathematica Symbol) Scan[f, expr] evaluates f applied to each element of expr in turn. Scan[f, expr, levelspec] applies f to parts of expr specified by levelspec.
SelectionCreateCell[notebook] copies the contents of the current selection in a notebook into a new cell. SelectionCreateCell[notebook, sel] sets the current selection after ...
SelectionEvaluate[notebook] replaces the current selection in a notebook with the result obtained by evaluating the contents of the selection in the kernel. ...
SetSystemOptions["name" -> value] resets the value for the internal system option with the specified name.
ShowCellLabel is an option for Cell that specifies whether to display the label for a cell.
Skeleton[n] represents a sequence of n omitted elements in an expression printed with Short or Shallow. The standard print form for Skeleton is <<n>>.
Slider2D[{x, y}] represents a 2D slider with settings x and y in the range 0 to 1. Slider2D[Dynamic[pt]] takes the setting to be the dynamically updated current value of pt, ...
SpanCharacterRounding is an option for selections that specifies the method used for rounding a spanning character when its size is to be adjusted.
StringFormat["string"] attempts to determine what ImportString format could be used to import the string " string".