A wallpaper or background (also known as a 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, smartphone or other electronic device. On a computer, wallpapers are generally used on the desktop, while on a mobile phone they serve as the background for the home screen. Though most devices include a default background image, modern devices usually allow users to manually change the background image.
The term "wallpaper" was used in Microsoft Windows before Windows XP (In Windows XP and later, it is called the "desktop background"). Meanwhile, macOS refers to it as "desktop picture". On older systems that allowed small repeated patterns to be set as background images, the term desktop pattern was used.