Woe in everyday things

Donald Norman, author of The Design of Everyday Things, impresses upon the reader the necessity that designs be made more conducive to a streamlined, simplified end-user experience. By simplified, he does not mean that items lose function or systems complexity; rather he wishes designs be made "easy to interpret and understand"--that is--more intuitive and user-friendly. To elaborate these ideas, Norman illustrates various principles: conceptual modeling, visibility, proper mapping/natural flow, and feedback.

Conceptual Modeling
Many devices of good design have some sort of conceptual modeling. This modeling provides the user some idea as to how the device may function based on rudimentary logic.

Visibility
Functions of complex designs should not be hidden in a sea of controls controlling other functions. Functions should be assigned non-arbitrary controls to a distinct ends.

Mapping
Controls should be located on a design in such a way to promote natural flow. In good design there is no requirement to position awkwardly just to make use of functions.

Feedback
Whether it be vibration, demarcation, buzz, or light, good design provides a way to determine if functions have been executed successfully.

I've encountered various designs over the years that have been less than intuitive. The most recent of these design blunders was a certain color-laser printer with fax capability. Sending faxes was quite difficult as the machine provided no tonal or (backlit) visual feedback as to which numbers had been pressed. Worst yet, the security capability required password authentication to send, not receive faxes.

In designing iPod, Apple not only considered, but successfully instituted the aforementioned principles. Despite being a complex design, iPod manages to provide for a simple, streamlined end-user experience. On a conceptual level, users young and old alike have some idea as to how the device functions by simply referring to basic logic. Moreover, controls are clearly yet unobtrusively labeled, mapped most intuitively, and follow a natural flow as to their function. The scroll wheel, in particular, holds true to these principles. Apple took the concrete knowledge that the clock moves in a right-bound circular fashion, increasing incrementally, and applied it to the scroll wheel. One simply moves the finger over it in a clockwise fashion to incrementally increase data/volume and conversely moves the finger in a counterclockwise fashion to incrementally decrease data/volume all the while providing tonal and visual (demarcated) feedback as to these actions.