Don't Make Me Think
Don't Make Me Think is a book by Steve Krug about human computer interaction and web usability. The book's premise is that a good program or web site should let users accomplish their intended tasks as easily and directly as possible. Krug points out that people are good at satisficing, or taking the first available solution to their problem, so design should take advantage of this. He frequently cites Amazon.com as an example of a well-designed site that manages to allow high quality interaction even though the site gets bigger and more complex every day.
The book itself is intended to be an example of concision and extremely well focused writing. The goal, according to the book's introduction, was to make a text that could be read by an executive on a two-hour flight.