A raster image is an assembly of individual pixels of color arranged to form an image, also known as bitmaps. From a visual design aspect, raster images are simple to make smaller, but making them larger is tricky. Increasing the size of a raster image decreases the resolution, making your picture look blurry or fuzzy. For example, the photos taken on your phone are raster images. If you zoom in close on a picture, you see the tiny grains or squares in the photo. So when with print that image with our HP Indigos they print the photo exactly, including those fuzzy pixels.