Page orientation

Page orientation is the way in which a rectangular page is oriented for normal viewing. The two most common types of orientation are portrait and landscape. The specific word definition comes from the fact that a close-up portrait of a person's face and upper body is more fitting for a canvas or photo where the height of the display area is greater than the width, and is more common for the pages of books. Landscape originally described artistic outdoor scenes where a wide view area is needed, but the upper part of the painting would be mostly sky and so is omitted.

Page orientation is also used to describe the dimensions of a video display. The most common video display orientation is landscape mode, especially the 4:3 ratio, which is 4 units wide and 3 units tall, and the more recent 16:9 widescreen landscape display mode.

Portrait screen orientation is also used for computer displays, though less commonly than landscape, and is the most popular orientation for mobile devices. Portrait is preferred for editing page-layout work, in order to view the entire page on the screen at once without wasted space along the sides, and for script-writing, legal work (in drafting contracts etc.), and other applications where it is useful to see a maximum number of lines of text. It is also common in public information displays.

Portrait mode was first used on the Xerox Alto computer, which was considered technologically well ahead of its time when the system was first developed. Xerox product marketers did not understand how revolutionary the system was, and the portrait display faded away while common landscape-display televisions were appropriated for use as an inexpensive early microcomputer display.

The IBM DisplayWriter had a portrait monitor and keyboard with large backspace key, as it was designed for use in word processing instead of spreadsheets. Lanier, Wang, and CPT also made competing dedicated word processing computers with portrait modes. The height of the market for these computes was the late 1970s and early 1980s, prior to the introduction of the IBM PC. However, according to a long-time regional manager of the IBM personal computer division, speaking in confidence to the author of this entry in the mid-1980s, when the IBM PC was introduced, no portrait mode was made available for two reasons: (1) Top management didn't want the PC division to undermine the DisplayWriter product, (2) The computer was designed with spreadsheets and software development in mind, not word processing. Thus, it had a keyboard without a large backspace key at first, substituting a key widely used in computer software writing. Within a short period of time, the DisplayWriter and other dedicated word processors were no longer available. However, Portrait Display Labs leaped into this market niche, producing a number of rotating CRT monitors as well as software which could be used as a driver for many video cards. The later advent of the World Wide Web, whose pages are largely in portrait mode, failed to result in a widespread return to portrait displays. As of November 2011, for instance, HP no longer sells monitors in portrait mode, although they have a display stand which permits the user to attach two monitors and rotate either from landscape to display.

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