Canon PowerShot S120 Manual (en)

Opening and Closing Window Panels (Panes)
Panels (panes) at the top, bottom, left, and right of each window can be 
closed to suit the tasks being performed.  
You can use DPP in an optimal layout. 
Click the [
] for a panel to open or close.
When a panel is closed, you can point to [
] with the mouse 
to temporarily open the panel.
Example: main window (thumbnail layout)