A paned window is a combination of two or more panes (control, text, draw area, or term panes, in any combination) into one virtual window with multiple panes, one above the other, separated by a movable sash. While the paned window maintains a constant height, the individual panes become smaller or larger as you move the sash between them.
A paned window's initial size and position are determined by the position and size of its panes: the left margin of the paned window is determined by the left (West) edge of the pane that is furthest to the left. The width of the paned window is determined by the width of its widest pane.
You can set limits on the minimum and maximum heights of any of the panes by setting Pane Height in the Paned Window property editor. See Appendix B, Revolving Property Editor for more details.
Once you have created a paned window you can resize the panes by pressing mouse button 1 or mouse button 2 on the sash and moving it up or down.