Different file formats store information in different ways. JPEG images are a compressed version of bitmaps. They reduce the size of the image file by removing information about the image which the human eye typically can’t detect. For instance, if you’re looking at an image on a 4k screen, your eye probably won’t notice if some of those 9 million pixels don’t have the exact same tone they had in the bitmap format. Since JPEG files compress the image, they take up far less space on your computer; however, they do so at the loss of overall quality.