Fractional calculus has applications in many fields of engineering and science such as * Visco-elasticity, * Fluid mechanics, * Biological models, * Psychology etc. For the accurate modeling of physical and engineering processes the fractional derivative models and techniques are found to be best and accurate to the experimental results. In this discussion I will give a brief introduction about the formulation of the fractional order derivative operators methods how to develop a model in the settings of fractional calculus from the classical ones.