EDM machining is a machining process that mainly uses a discharge electrode (EDM electrode) with a specific geometry to burn out the geometry of the electrode on a metal (conductive) part.

The difference between EDM and general cutting, and one of the greatest advantages of EDM, is that the tool and the workpiece are not in contact during EDM, but instead rely on the continuous pulse discharge between the tool and the workpiece. The local and instantaneous high temperature generated by the discharge is used for gradually corrosion removing the metal material. Because there are visible sparks during the discharge process, it is called EDM.

Spark Erosion, also known as electrical discharge machining, is a manufacturing process which creates a specific shape using electrical discharges (sparks). Spark erosion removes material from a piece with current discharges between two electrodes that are separated by a dielectric liquid that is subject to voltage. The dielectric fluid acts as a conductor and a cooling agent during the sparking process.