Glossary » window
an area of a computer screen, used for representing an application or document or for any other set of related interface elements. Graphics drawn to a window are clipped to its frame.
“Overlapping windows” are the most common in GUIs. They can be moved and resized, and windows can be brought forward, obscuring windows behind them.
“Tiled windows” are a way of dividing up the screen into panes (as in split windows, or web-browser frames). With tiled windows, users have much less control over the position and size of the windows, though this may make interaction even easier.