Task-Centered Human Interface Design
The central goal of this online shareware book is to teach the reader how to design user interfaces that will enable people to learn computer systems quickly and use them effectively, efficiently, and comfortably. The interface issues addressed are primarily cognitive, that is, having to do with mental activities such as perception, memory, learning, and problem solving. (2000-02-06)
The link address is: http://www.acm.org/~perlman/uidesign.html