As of Version 7.0, FourierCoefficient is part of the built-in Mathematica kernel.
As of Version 7.0, FourierSeries is part of the built-in Mathematica kernel.
As of Version 7.0, InverseDTFourierTransform has been renamed to InverseFourierSequenceTransform and is part of the built-in Mathematica kernel.
As of Version 7.0, SpheroidalDistance has been superseded by GeoDistance.
As of Version 7.0, Histogram3D is part of the built-in Mathematica kernel.
As of Version 7.0, HistogramCategories has been superseded by an optional argument hspec for the built-in Mathematica function Histogram.
Histogram
(Obsolete Histograms Package Symbol) As of Version 7.0, Histogram is part of the built-in Mathematica kernel.
As of Version 7.0, DesignMatrix is part of the built-in Mathematica kernel.
As of Version 8, PrincipalComponents is part of the built-in Mathematica kernel.
As of Version 7.0, PieExploded has been superseded by SectorSpacing.