This only makes sense if the file has been zoomed. You can now click to interactively move right to the portion of the sound file you want to see on-screen. Each click moves the position by 80% of the total visible window. A position bar at the top of the graphical window shows the relative position of the display with respect to the complete file and also shows the current selection, if any exists.
The Scroll Right command can also be activated by clicking on 
in the toolbar section.