ECM is an unconventional process of machining which is also known as the reverse Electroplating process used to machine conductive material in the presence of electrolyte with the help of a controlled reaction between tool and workpiece. In recent times ECM machines are usually used for machining hard and complex shapes materials like composites, ceramic, Inconel etc. which have applications in space industries, Automobiles, medical, and railways. Because they are less dense than conventional metals, have high mechanical qualities, are more resistant to corrosion and wear, and have a lower thermal expansion coefficient. Considering the processes and their parameters related to Electrochemical machining. Few of the existing literature reviews are presented in this study. This study compiles the latest research concerning the electrochemical machining of MMC and metal alloys. New techniques include electrode design, abrasive particle reinforcement, electrolyte flow rate etc.