## ABSTRACT

There are two types of systems-discrete and continuous. In a discrete system, the state variables’ values change at discrete points in time, whereas in a continuous system, the state variables’ values change continuously over time. The state variable of a system describes the state that reects the values of the variables. Experiments are conducted to nd the states of a dened system. Experimentation can be done on the actual system or a prototype of the system. If the actual system is large, it is difcult to observe the functioning of each of the components. On the contrary, developing a representative prototype for the system is a difcult task. If prototyping is not done properly, the purpose of simulation study will be in vain. There are two types of prototypes-physical and mathematical [1], also known as physical models and mathematical models, respectively. A physical model is a miniature of the actual system, whereas a mathematical model emphasizes only mathematics to represent the system on hand. Mathematical models can further be subdivided into two types: analytical systems, which use hardcore mathematical expressions to represent the working of a system, and simulation systems, which use mathematics but not in the form of explicit mathematical expressions. Simulation is entirely dependent on the uncertainties of a real system and thus uses probability distributions wherever

the condition of uncertainty is applicable. Figure 1.1 shows the type of experimentation that can be conducted to study a system.