User portability in open systems

The open systems concept in the design of computer-based systems has become accepted as a method for developing cost-effective systems. One goal of open systems design within the U.S. Department of Defense is user portability. User portability can be described as the ability of users to move from one application or system to another, with minimal difficulties. It is accomplished by applying style guide principles and user interface specifications concurrently with user-centered design. The key factor for integrating these into the design process is the use of human factors engineering