Meaning and importance of simulation and modelling, classification of models, Variables and problem formulation, performance measures, Data collection and analysis, SIMSCRIPT language concept: general syntax, Discrete event modelling, process and resources, timing and pending list, accumulate and tally, process instance and object oriented aspects, sets and data structures, Probability distribution, Random number and random variant generation. Input modelling and output analysis. Generation of graphical output, user interface and animation in SIMSCRIPT, development of simulation models of real system through integration of programming and statistical concepts, issues related to credibility of models.