US Patent 7075513 Zooming and panning content on a display screen

A method and system for manipulating content displayed on a display screen is disclosed. A data processing device has two attached user input controls, such as touch pads, joysticks, and the like. One of the controls may be used for panning (i.e. scrolling up and down and/or left and right) content on the display screen, while the other control may simultaneously be used for zooming in and zooming out of content as it is displayed on the display screen. The zoom and pan increment levels may be smooth or stepped, depending on a user preference, to aid in navigation of the content displayed on the display screen.