DefaultNewCellStyle is a notebook option which specifies the default style to use for new cells created in the notebook.
Denominator[expr] gives the denominator of expr.
DepthFirstScan[g, s, {"event_1" -> f_1, "event_2" -> f_2, ...}] performs a depth-first scan of the graph g starting at the vertex s and evaluates f_i whenever "event_i" ...
DGaussianWavelet[] represents a derivative of Gaussian wavelet of derivative order 2.DGaussianWavelet[n] represents a derivative of Gaussian wavelet of derivative order n.
DialogProlog is an option for Dialog that can give an expression to evaluate before the dialog starts.
DialogSymbols is an option for Dialog which gives a list of symbols whose values should be localized in the dialog.
DisplayAllSteps is an option to Animate and related functions that specifies whether all frames should be displayed in an animation, even if to do so would slow the animation ...
ExcludePods is an option to WolframAlpha that specifies pod IDs to exclude from the results.
Exit
(Built-in Mathematica Symbol) Exit[] terminates a Mathematica kernel session.
FeedbackType is an option for some control system functions that specifies the feedback type.