FinishDynamic[] finishes updating and displaying all currently visible Dynamic objects.
First
(Built-in Mathematica Symbol) First[expr] gives the first element in expr.
FontColor is an option for Style, Cell, and related constructs that specifies the default color in which to render text.
FontVariations is an option for Style, Cell, and related constructs that specifies what font variations should be used.
FrameBox[box] is a low-level box construct which represents box with a frame drawn around it.
FromCoefficientRules[list, {x_1, x_2, ...}] constructs a polynomial from a list of rules for exponent vectors and coefficients.
FrontEndTokenExecute["cmd"] executes the specified front end command token, typically corresponding to a front end menu item.
FullGraphics[g] takes a graphics object, and generates a new one in which objects specified by graphics options are given as explicit lists of graphics primitives.
GapPenalty is an option for SequenceAlignment and related functions that gives the additional cost associated with each gap corresponding to a run of insertions or deletions.
GenerateConditions is an option for Integrate, Sum, and similar functions that specifies whether explicit conditions on parameters should be generated in the result.