Abstract: The objective of this paper is to understand various trends of Electrical discharge machining (EDM) has been widely used as a removal process to produce parts, dies and molds for several decades. In recent years, the surface modification for hardening and depositing some functional materials by EDM has been studied [1].The development of the super tough electrical conductive material such as carbides, stainless steel, nitralloy etc. resulted in development of the nontraditional machining processes. These materials are difficult to machine by conventional machining process & have wide range of applications in industry.