Linked by Thom Holwerda on Sun 16th Sep 2007 12:59 UTC, submitted by anonymous
"The HTML file that contains all the text for this article is about 25000 bytes. That's less than one of the image files that was also downloaded when you selected this page. Since image files typically are larger than text files and since web pages often contain many images that are transmitted across connections that can be slow, it's helpful to have a way to represent images in a compact format. In this article, we'll see how a JPEG file represents an image using a fraction of the computer storage that might be expected. We'll also look at some of the mathematics behind the newer JPEG 2000 standard."