What is Electrical Discharge Machining (EDM) used for?

Electrical Discharge Machining (EDM) is a precision machining process that involves the use of electrical discharges to erode (or remove) material from a workpiece. This technique is particularly effective for shaping hard metals and can create intricate designs that would be difficult or impossible to achieve with traditional machining methods. The process utilizes a series of rapid electrical sparks between an electrode and the workpiece, which result in small amounts of material being removed, allowing for fine detailing and tight tolerances.

In the context of the provided options, the primary characteristic of EDM is its ability to erode material in a controlled manner, making option C the most accurate description of its function. This capability makes EDM favorable for creating complex shapes, holes, and contours in hard materials without applying significant mechanical stress that could lead to tool wear or damage.