StarGraph[n] gives the star graph with n vertices S_n.
s_1 ~~ s_2 ~~ ... or StringExpression[s_1, s_2, ...] represents a sequence of strings and symbolic string objects s_i.
SubMinus[expr] displays as expr_-.
SubPlus
(Built-in Mathematica Symbol) SubPlus[expr] displays as expr_+.
Subsuperscript[x, y, z] is an object that formats as x_y^z.
x -= dx subtracts dx from x and returns the new value of x.
Superscript[x, y] is an object that formats as x^y.
SystemOpen["target"] opens the specified file, URL, or other target with the associated program on your computer system.
SystemOptions["name"] gives the current setting for the internal system option with the specified name.SystemOptions[] gives the current settings for all settable internal ...
TextData[exprs] is a low-level representation of the contents of a textual cell.