Figure 17-8. http://www.cnn.com
CNN (http://www.cnn.com) is the heaviest of the 10 top web sites in both total page weight (502K) and number of HTTP requests (198!). The main reason for this is the use of images to display text. For example, the image http://i.a.cnn.net/cnn/element/img/1.5/main/tabs/topstories.gif is the text "Top Stories," as shown in Figure 17-9.
Figure 17-9. Text rendered in an image
Over 70 images contain only text. Capturing text as an image allows for a customized appearance that may not be possible with text fonts. The tradeoff, as seen in the download statistics, is an increase in page weight and HTTP requests, resulting in a slower user experience. Also, internationalization is more challenging, as each translation requires a new set of images. Rule 1 tells us that reducing the number of components is the most important step to faster performance. Replacing these images with text would yield the biggest performance improvement for this page.
Further, more than 140 of the components in the page ...