The Horizontal splitter weblet divides the area covered by the weblet into a top and bottom pane with a moveable divider separating the two panes. It does not provide any input or output but is used solely to assist with web page design. Other elements or weblets can be dropped into each pane, effectively creating multiple editable areas on the web page.
The horizontal splitter can be combined with additional horizontal splitters or vertical splitters to construct more complex pages.
It looks like this: