Accuracy[x] gives the effective number of digits to the right of the decimal point in the number x.
ActionMenu[name, {lbl_1 :> act_1, lbl_2 :> act_2, ...}] represents an action menu with label name and with items labeled lbl_i that evaluates the expression act_i if the ...
Active
(Obsolete Mathematica Symbol) As of Version 6.0, Active has been superseded by Enabled.
ActiveStyle is an option for Hyperlink and related constructs that specifies styles to add when the constructs are active, typically as a result of the mouse being over them.
AcyclicGraphQ[g] yields True if the graph g is an acyclic graph and False otherwise.
AddOnHelpPath is a global option that specifies which directories are searched for additional help files used within the help system.
AdjacencyGraph[amat] gives the graph with adjacency matrix amat.AdjacencyGraph[{v_1, v_2, ...}, amat] gives the graph with vertices v_i and adjacency matrix amat.
AdjustmentBox[box, opts] is a low-level box construct which displays with the placement of box adjusted using the options given.
AffineTransform[m] gives a TransformationFunction that represents an affine transform that maps r to m.r. AffineTransform[{m, v}] gives an affine transform that maps r to m.r ...
AlgebraicNumberDenominator[a] gives the smallest positive integer n such that n a is an algebraic integer.