ABSTRACT
Human error and software bugs have become a pressing issue in computer systems because of problems such as high cost, catastrophic failures, and incorrect decisions and actions. For example, a study commissioned by the U.S. Department of Commerce’s National Institute of Standards and Technology (NIST) in 2002 reported that software bugs or errors alone cost the U.S. economy about $59 billion annually (i.e., around 0.6% of its gross domestic product (GDP) [1]. Furthermore, in regard to catastrophic failures, in 1996 the European Space Agency’s US$1-billion prototype Ariane 5 rocket was destroyed just forty seconds after launch due to a bug in the onboard guidance computer program [2].
