Animator[u] represents an object that displays with the value of u being continually increased from 0 to 1 with time. Animator[u, {u_min, u_max}] makes u vary from u_min to ...

FullForm[expr] prints as the full form of expr, with no special syntax.

PopupView[{expr_1, expr_2, ...}] represents an object which displays as a popup menu whose items are the expr_i.PopupView[{expr_1, expr_2, ...}, i] makes the i\[Null]^th ...

Riffle[{e_1, e_2, ...}, x] gives {e_1, x, e_2, x, ...}. Riffle[{e_1, e_2, ...}, {x_1, x_2, ...}] gives {e_1, x_1, e_2, x_2, ...}. Riffle[list, x, n] yields a list in which ...

Tuples[list, n] generates a list of all possible n-tuples of elements from list. Tuples[{list_1, list_2, ...}] generates a list of all possible tuples whose i\[Null] ...

This is the J/Link scribble pad example implemented with the GUIKit` package.

ShowGraph[g] displays the graph g. ShowGraph[g, Directed] is obsolete and it is currently identical to ShowGraph[g].

LegendBackground is an option for Legend, which specifies the style of background to use with a legend.

LegendBorder is an option for Legend, which specifies the style of the line surrounding key boxes and text in a legend.

LegendTextDirection is an option for Legend, which specifies the direction of text next to the key box.