LabelingFunction is an option for charting functions that specifies a function to apply to determine labeling of chart elements.
PaneSelector[{v_1 -> expr_1, v_2 -> expr_2, ...}, v] represents an object that displays as a pane containing the expr_i for which v_i is equal to v.
Defer
(Built-in Mathematica Symbol) Defer[expr] yields an object that displays as the unevaluated form of expr, but that is evaluated if it is explicitly given as Mathematica input.
Sequence[expr_1, expr_2, ...] represents a sequence of arguments to be spliced automatically into any function.
ImageResolution is an option for Export, Rasterize, and related functions that specifies at what resolution bitmap images should be rendered.
EaseOfMovement
AlternativeHypothesis is an option for hypothesis testing functions like LocationTest that specifies the alternative hypothesis.
EdgeLabeling is an option for GraphPlot and related functions that specifies whether labeling specified for edges should be displayed by default.
FileType["file"] gives the type of a file, typically File, Directory, or None.
HammingDistance[u, v] gives the Hamming distance between strings or vectors u and v.