Human Factors are principles and theories based on the way individuals operate, remember, read, or learn things. Human Factors has played a major role in the design of instruments and gages for airplanes, various machinery, and automobiles. Researchers and teachers in cognitive psychology and ergonomics have also used the theories to study the way people develop and learn.

In recent years, it has played an important role for software engineers as they develop and design computer software. However, as technical writers, editors and graphic designers become more involved in the process of designing user interfaces, icons, and multimedia, as well as conducting usability tests, they need to learn (and quickly!) the human factors foundations that were not part of their initial education or training.