DefaultNewCellStyle is a notebook option which specifies the default style to use for new cells created in the notebook.

ImageAssemble[{{image_11, image_12, ...}, {image_21, ...}, ...}] assembles a single image from an array of images.

InitializationGroup is an option for the first cell of a cell group that specifies whether the group should be tagged to be evaluated by the Mathematica kernel when the ...

MessagePacket[symbol, string] is a MathLink packet containing a Mathematica message identifier of the form symbol::string.

Order[expr_1, expr_2] gives 1 if expr_1 is before expr_2 in canonical order, and -1 if expr_1 is after expr_2 in canonical order. It gives 0 if expr_1 is identical to expr_2.

Plain represents a font that is not bold, italic, or underlined.

ReturnTextPacket[string] is a MathLink packet containing string, the result of an EnterTextPacket evaluation.

SameTest is an option whose setting gives a pairwise comparison function to determine whether expressions should be considered the same.

ShowClosedCellArea is an option for cells that specifies whether a rectangular bar is displayed next to a closed cell group to indicate the number of cells in the group.

ShowPageBreaks is a notebook option that specifies whether to indicate in the on-screen display of a notebook where page breaks would occur if the notebook were printed.