MatrixPlot[m] generates a plot that gives a visual representation of the values of elements in a matrix.
Messages[symbol] gives all the messages assigned to a particular symbol.
Module
(Built-in Mathematica Symbol) Module[{x, y, ...}, expr] specifies that occurrences of the symbols x, y, ... in expr should be treated as local. Module[{x = x_0, ...}, expr] defines initial values for x, ...
NonConstants is an option for D which gives a list of objects to be taken to depend implicitly on the differentiation variables.
NotebookPath is a global option that determines which directories are searched when a specified notebook is needed.
NumberPadding is an option for NumberForm and related functions which gives strings to use as padding on the left- and right-hand sides of numbers.
Overlaps is an option to StringCases, StringCount, and StringPosition that specifies how to treat overlapping substrings.
PasteBoxFormInlineCells is an option for cells that specifies whether a new inline cell is created when a typeset expression is pasted into a non-box-type cell.
PrintTemporary[expr] prints expr as a temporary cell in a notebook, removing it when the evaluation of the current input line is complete.
RecordLists is an option for ReadList that specifies whether objects from separate records should be returned in separate sublists.