A desktop wallpaper is an image that loads on your computer screen shortly after booting up your computer. These images can be just about anything, from a picture of a beach to a photo of your friends. By default, many computers have their desktop wallpapers automatically stretch to fill their monitor. This can cause blurry images in those who have large monitors or a high screen resolution. Fortunately, you don't have to settle on picking a different background image. Instead, you can change the way your computer displays the image, allowing the image to become unblurred.