Introduction

Abstract

Computer-based models and simulations have been in use as long as there have been digital computers. The value of M&S technologies throughout history is without question. However, the development and use of reliable computer models and simulations is today time consuming, expensive, and can sometimes produce unreliable results. These issues become even more critical as engineered systems increase in complexity and scale and must be deployed in uncertain environments. Advances in M&S technologies now are essential to enable the creation of more effective, robust, and less costly engineered complex systems that are critical to modern societies. This first chapter begins by examining why advances in M&S are particularly important now. Key terminology is defined. It then frames the discussions covered in the remaining chapters by characterizing the role of each within the life cycle for a modeling and simulation study.