The more a computer knows about a user, the better it can serve that user. But there are different styles, and even philosophies, of how to teach our computers about us-about our habits, interests, patterns, and preferences. But it is also an exhortation for readers to incorporate the described techniques and philosophy into their own systems. User modeling is nothing more than a fancy term for automated personalization.
Humans model each other all the time.
If I have guessed well, you will enjoy this essay. If not, you will skip to the next one. That is what user modeling systems do-they make guesses, and hopefully educated ones, about their users. Of course, not all readers are the same, and what entices one reader may alienate another. Ideally, this essay would itself be adaptive, able to gauge the interests of individual readers and transform itself accordingly.