Users spend most of their time on other sites. This means that users prefer your site to work the same way as all the other sites they already know.

Even better than good error messages is a careful design which prevents a problem from occurring in the first place. Either eliminate error-prone conditions or check for them and present users with a confirmation option before they commit to the action.

Windows '98 is so similar to Windows '95 because Apple hasn't invented anything worth copying since 1995.

Throughout this book, we've been evangelizing simplicity, but ironically, the practice of simplicity is not simple. It is easy to build a bulky design by adding layer upon layer of navigation and features; it's much more difficult to create simple, graceful designs. Paring designs to essential elements while maintaining elegance and functionality requires courage and discipline.

Three Tips: Simplify, Simplify, Simplify.

Diversity is power on the Web. Big sites may be bigger, but smaller sites will keep scoring higher for specialized topics, both in terms of their connections with users and in terms of each visit's commercial value.

Popularity is the product of two factors: (a) how compelling material you offer, and (b) how easy it is to access it. Host free pirated movies and users will flock to the site, even if it's difficult to use.