ShowSelection is an option to Notebook, Cell, and Style that specifies whether to show the current selection highlighted.

Visible is a notebook option which specifies whether the notebook should be explicitly displayed on the screen.

Fundamental to Mathematica's dynamic interactivity capabilities is a new form of symbolic dynamic language. With a very small number of highly powerful primitives that mix ...

FormBox[boxes, form] is a low-level box construct which displays as boxes but specifies that rules associated with form should be used to interpret boxes on input.

NotebookPut[expr] creates a notebook corresponding to expr and makes it the currently selected notebook in the front end. NotebookPut[] creates a new empty ...

ScriptSizeMultipliers is an option for Style that specifies how much smaller to render each successive level of subscripts, etc.

RawData[data] is a low-level representation of the contents of a cell in which Show Cell Expression has been toggled.

StyleBox[boxes, options] is a low-level representation of boxes to be shown with the specified option settings. StyleBox[boxes, " style"] uses the option setting for the ...

Reading and Writing Mathematica Files External Programs Streams and Low-Level Input and Output