Chapter 19. Content

In the end, the Web is about content. The browser, server, and network are all working towards one goal: to push bits from one end to the other. This chapter is about what you can do on the content end to make this happen as quickly as possible.

Size Matters

The network doesn’t know or care what type of content you are serving. Bits are bits. Size is all that really matters for network transfer time. Therefore, the most basic performance principle is to send fewer bits and make fewer requests. Try to think of size in terms of download time rather than absolute bits, because how long a human being has to wait is the ultimate measure of success. If most of your users are on 28.8 modems, make a rule that no image can be “larger” than ten seconds. Ten seconds is about 35K if a 56K modem is running well.

Compare Yahoo! (, which has a very light home page, to CNN (, which tends to bloat. The difference in download time is significant. It’s easy to get carried away, so lay down some ground rules and try to get your content developers to care about bandwidth issues. Another example of excellent (i.e., minimal) design is Craig’s List, at

I personally like all of the web designers I’ve met, and yet I can’t help cringing when I run into them because I spend a lot of my time complaining about their work. Designers like to design, and that usually means writing flashy pages without any consideration ...

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