ColumnLines is an option for GridBox which specifies whether lines should be drawn between adjacent columns.
The default setting is ColumnLines->False.
ColumnLines->, , ... specifies whether lines should be drawn between successive pairs of columns. The can be True or False.
If there are more columns than entries in the list, the last element is used repeatedly for remaining pairs of columns.
Lines can be drawn around the outside of a GridBox using FrameBox.
See Section 2.9.10.
See also: RowLines, FrameBox, GridLines.
New in Version 3.