EDM is the non-conventional process that has used, extensively, for cutting harder like nickel and its alloys, titanium and complex shape materials which are difficult to machine by other conventional processes. EDM utilizes, electrical and heat, energy to machine the workpiece by removing the undesirable material. This process use two electrodes, anode and cathode out of which tool act as cathode and the workpiece on which the job is being performed act as anode. Various factors like current, pulse on and off time, voltage applied can be used to optimize the major machining parameters of EDM like MRR, rate of tool wear, surface roughness etc. the main focus of this study these parameters on composite materials made of CMs, tungsten and cobalt carbides etc. In the end future prospective of the areas which require further improvements and investigations has also been discussed.