Designing a User Interface There’s a big difference between knowing the elements of a user interface and knowing how to put together an effective user interface. That’s like the difference between knowing how to write every letter of the alphabet and knowing how to write a best-selling novel. That’s why designing a user interface is part art and part science. After you design enough user interfaces and use the user interfaces of different programs, you can see what you like and don’t like. Then you can apply your own ideas to designing your idea of a perfect user interface. Although it’s difficult to teach the art of designing a user interface, it’s much easier to teach the science behind designing a user interface.
By following certain user interface principles, you can increase the chances that your user interface will at least be competent and usable. To see drastic differences between user interfaces, compare the user interfaces of commercial programs from Microsoft, Adobe, or Apple and then look at the user interfaces on shareware, freeware, or niche commercial pro- grams (such as astrology charting programs or horse race prediction pro- grams).
Big companies spend much time and money testing their user interfaces. In comparison, many individual programmers just slap together a user interface and start selling their program — and the results from their user interface really shows the difference.