SphericalHarmonicY[l, m, \[Theta], \[Phi]] gives the spherical harmonic Y_l^m(\[Theta], \[Phi]).
SplineWeights is an option for B-spline functions and graphics primitives that specifies weights of control points.
SquareWave[x] gives a square wave that alternates between +1 and -1 with unit period.SquareWave[{y_1, y_2}, x] gives a square wave that alternates between y_1 and y_2 with ...
StreamColorFunction is an option for StreamPlot and related functions that specifies a function to apply to determine colors along streamlines.
StringDrop["string", n] gives " string" with its first n characters dropped. StringDrop["string", -n] gives " string" with its last n characters dropped. StringDrop["string", ...
Trigger
(Built-in Mathematica Symbol) Trigger[Dynamic[u]] represents a trigger that can be pressed to make the dynamically updated value of u be continually increased with time from 0 to 1. Trigger[Dynamic[u], ...
VarianceEstimatorFunction is an option for LinearModelFit and NonlinearModelFit which specifies the variance estimator to use.
When you do long calculations, it is often convenient to give names to your intermediate results. Just as in standard mathematics, or in other computer languages, you can do ...
Partial differentiation operations. This gives ( ∂ ) / ( ∂x ) x^n. This gives the third derivative.
Elementary transcendental functions. Mathematica gives exact results for logarithms whenever it can. Here is log_21024. You can find the numerical values of mathematical ...