NullWords (Built-in Mathematica Symbol)

NullWords is an option for Read and related functions which specifies whether null words should be taken to exist between repeated word separators.

Number (Built-in Mathematica Symbol)

Number represents an exact integer or an approximate real number in Read.

NumberString (Built-in Mathematica Symbol)

NumberString represents the characters of a number in StringExpression.

OperatingSystem (Built-in Mathematica Symbol)

OperatingSystem is an option for file and related operations that specifies the type of operating system to use to determine file name and other conventions.

OutputAutoOverwrite (Built-in Mathematica Symbol)

OutputAutoOverwrite is an option for notebooks that specifies whether the output of a command should replace any existing output from a previous evaluation.

OutputNamePacket (Built-in Mathematica Symbol)

OutputNamePacket[string] is a MathLink packet that contains in string the name assigned to the next output.

OverDot (Built-in Mathematica Symbol)

OverDot[expr] displays with a dot over expr.

Overflow (Built-in Mathematica Symbol)

Overflow[] represents a number too large to represent explicitly on your computer system.

OverHat (Built-in Mathematica Symbol)

OverHat[expr] displays with a hat over expr.

OverscriptBoxOptions (Built-in Mathematica Symbol)

OverscriptBoxOptions -> {opt_1 -> val_1, opt_2 -> val_2, ...} is an option that specifies the style and display of OverscriptBox constructs.