Bitmap images also known as raster images are created or captured as a grid of colored dots called pixels. A pixel (short for picture element) is the smallest unit of space in a digital photo, a computer screen, or a printed image. Each pixel is a square that has a specific location and color. When working with bitmap images such as those in FotoFinish, you create and edit pixels.
Because a bitmap image contains a finite number of pixels, its appearance depends on its resolution Resolution refers to the total number and density of pixels available in the image. If you stretch a bitmap image, it will lose detail and quality. The image below is magnified to show how a bitmap image can become jagged and blurry when you zoom in or print it at too large a size.
A bitmap image becomes jagged (pixilated) when viewed or printed at a larger size