Graphics
http://www.webstyleguide.com/graphics/

Lynch, Patrick J. and Sarah Horton
Yale University
1999

Abstract:

In this chapter we show you techniques to optimize the look and efficiency of your Web page graphics. Although electronic publishing frees you from the cost and limitations of color reproduction on paper, you will still need to make careful calculations (and a few compromises) if you wish to optimize your graphics and photographs for various display monitors and Internet access speeds.