Boole
(Built-in Mathematica Symbol) Boole[expr] yields 1 if expr is True and 0 if it is False.
CompiledFunction[args...] represents compiled code for evaluating a compiled function.
InverseFunction[f] represents the inverse of the function f, defined so that InverseFunction[f][y] gives the value of x for which f[x] is equal to y. InverseFunction[f, n, ...
FunctionInterpolation[expr, {x, x_min, x_max}] evaluates expr with x running from x_min to x_max and constructs an InterpolatingFunction object which represents an ...
DisplayFunction is an option for graphics and sound functions that specifies a function to apply to graphics and sound objects before returning them.
NearestFunction[data] represents a function whose values give the elements closest to an element that is supplied.
NormalsFunction is an option for Plot3D and related functions that specifies a function to apply to determine the effective surface normals at every point.
CounterFunction is an option for counters that specifies the symbols used to display the value of the counter.
ColorFunction is an option for graphics functions that specifies a function to apply to determine colors of elements.
RegionFunction is an option for plotting functions that specifies the region to include in the plot drawn.