The firefly algorithm is a recent nature inspired technique which mimics the behaviour of fireflies. Fireflies flash light in the sky in summer in tropical and temperate regions during night. This flash of light is the mode of communication between fireflies. Firefly with less light intensity flashes are attracted towards high intensity flashes of fireflies. Light intensity changes with distance from other fireflies and some intensity is lost in medium. As algorithm mimics the behavior of fireflies, the solution of any problem is evaluated in terms of light intensity in the presence of some variables for light intensity lost and distance between fireflies. For simplicity in describing FA, the following three idealized rules are framed [19-21]: