Built-in Mathematica Symbol

Pane

Pane[expr]
displays as a pane containing expr.

Pane[expr, w]
makes the pane be w printer's points wide, line-wrapping the contents if necessary.

Pane[expr, {w, h}]
makes the pane be w points wide, and h points high, shrinking the contents if necessary.

Alignment	{Automatic,Automatic}	how to align objects in the display area
BaselinePosition	Automatic	what to align with a surrounding text baseline
BaseStyle	{}	base style specifications for the pane
ImageMargins	0	margins to add outside the display area
ImageSize	Automatic	the overall image size of the displayed pane
ImageSizeAction	Automatic	what to do if the content size does not match the image size

With a typical default stylesheet, Pane[expr] with no additional options displays exactly like expr.

Pane[expr, w] is equivalent to Pane[expr, ImageSize->w, ImageSizeAction->"Clip"].

Pane[expr, {w, h}] is equivalent to Pane[expr, ImageSize->{w, h}, ImageSizeAction->"ResizeToFit"].

The settings for BaseStyle are appended to the default style typically given by the "Pane" style in the current stylesheet.

Wrap at a 200 point width: