Spark erosion machine has significant impact for machining of harder work pieces, it was only option in industries to remove material from hardened jobs like die tools and press tools. This paper is about machining of Inconel 718 alloy with different techniques by spark erosion process. The limited thermal conductivity of hard-to-machine materials makes it impossible for standard twist drills to build highly precise micro components on them. Because of its exceptional strength at the highest temperature, Inconel 718 super alloy is utilised to make aeronautical components. Response parameters like surface roughness and material removal rate were observed for each and every kind of approach are mentioned clearly. It gives clear picture of recent studies of machining of Inconel 718 alloy by spark erosion process and also shows research gaps to explore more in specific by altering different input conditions to optimise the process parameters.