A computer simulation or a computer model is a computer program that attempts to simulate an abstract model of a particular system. Computer simulations have become a useful part of mathematical modeling of many natural systems in physics, chemistry and biology, human systems in economics, psychology, and social science and in the process of engineering new technology, to gain insight into the operation of those systems. Traditionally, the formal modeling of systems has been via a mathematical model, which attempts to find analytical solutions to problems which enables the prediction of the behavior of the system from a set of parameters and initial conditions. Computer simulations build on, and are a useful adjunct to purely mathematical models in science, technology and entertainment. The reliability and the trust people put in computer simulations depends on the validity of the simulation model. Computer simulation is used to reduce the risk associated with creating new systems or with making changes to existing ones. More than ever, modern organizations want assurance that investments will produce the expected results. For instance, an assembly line may be required to produce a particular number of autos during an eight hour shift. Complex, interacting factors influence operation and so powerful tools are needed to develop an accurate analysis. Over the past few decades, computer simulation software, together with statistical analysis techniques have evolved to give decision makers tools equal to the task. As the world grows more technical and the need for precision becomes more important, the margin for error will continue to shrink. Business, industry, and governments cannot afford to make educated guesses during systems development. For that reason, computer simulation is more important than ever. Simulation models are a major tool for…