On a computer, wallpapers are generally used on the desktop, while on a mobile phone they serve as the background for the home screen. Decorative background on electronic devices A computer screen showing a background wallpaper photo of the Palace of Versailles A wallpaper from fractalĪ 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.