Computer wallpaper

A wallpaper or background (also known as a desktop wallpaper, desktop background, desktop picture or desktop image on computers) is a digital image (photo, drawing etc.) used as a decorative background of a graphical user interface on the screen of a computer, mobile communications device or other electronic device. On a computer it is usually for the desktop, while on a mobile phone it is usually the background for the 'home' or 'idle' screen. Though most devices come with a default picture, users can usually change it to custom files of their choosing.

"Wallpaper" was the term used in Microsoft Windows before Windows Vista (where it is called the "desktop background"), while Mac OS X calls it "desktop picture". (Previously, the term desktop pattern was used to refer to a small pattern that was repeated to fill the screen.)

Wallpaper images are usually copyrighted as many other digital images found on the Internet, and as such, most websites collecting and sharing wallpapers, as well as the users downloading from them are an example of mass copyright infringement, a phenomenon which challenges the meaning and illegality of digital piracy and the validity of current copyright legislation around the world.

The X Window System was one of the earliest systems to include support for an arbitrary image as wallpaper via the xsetroot program, which at least as early as the X10R3 release in 1985 could tile the screen with any solid color or any binary-image X BitMap file. In 1989, a free software program called xgifroot was released that allowed an arbitrary color GIF image to be used as wallpaper, and in the same year the free xloadimage program was released which could display a variety of image formats (including color images in Sun Rasterfile format) as the desktop background. Subsequently, a number of programs were released that added wallpaper support for additional image formats and other features, such as the xpmroot program (released in 1993 as part of fvwm) and the xv software (released in 1994).

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