MatrixPlot[m] generates a plot that gives a visual representation of the values of elements in a matrix.
SpheroidalPSPrime[n, m, \[Gamma], z] gives the derivative with respect to z of the angular spheroidal function PS n, m (\[Gamma], z) of the first kind.
SpheroidalQSPrime[n, m, \[Gamma], z] gives the derivative with respect to z of the angular spheroidal function QS n, m (\[Gamma], z) of the second kind.
StringDrop["string", n] gives " string" with its first n characters dropped. StringDrop["string", -n] gives " string" with its last n characters dropped. StringDrop["string", ...
StringFreeQ["string", patt] yields True if no substring in " string" matches the string expression patt, and yields False otherwise. StringFreeQ["string", {patt_1, patt_2, ...
StringReplacePart["string", " snew", {m, n}] replaces the characters at positions m through n in " string" by " snew". StringReplacePart["string", " snew", {{m_1, n_1}, {m_2, ...
SyntaxInformation[f] gives information used to generate syntax coloring and other advisories when f[...] is entered as input.
SystemDialogInput["type"] brings up an interactive system dialog and returns the value chosen in the dialog. SystemDialogInput["type", init] uses init as the initial setting ...
TagBox
(Built-in Mathematica Symbol) TagBox[boxes, tag] is a low-level box construct that displays as boxes but maintains tag to guide the interpretation of boxes on input.
TaggingRules is an option for selections that specifies a list of strings to be associated with a selection.