Portrait mode may refer to any of the following:
1. With graphics or printing, portrait mode is the orientation of the page that prints the image vertically across the page instead of horizontally. By default, all programs have the page orientation and printer pages set up in portrait mode. The image is an example of the printer paper orientation set up through the printer options in Microsoft Windows. The top example is a paper orientation selected as Portrait, and the bottom is selected as Landscape.
When in portrait mode, the page is taller than it is wide. When in landscape mode, the page is wider than it is tall.
3. With computer monitors, portrait mode refers to a monitor that is longer vertically than horizontally. Monitors mounted this way are popular amongst programmers, allowing for displaying more code on the screen. The image below shows a portrait-oriented monitor. Most monitors can be flipped to portrait mode, if preferred.