What are the two main types of machining operations?

The correct answer identifies the two main categories of machining operations: subtractive machining and additive machining. Subtractive machining involves the removal of material from a workpiece to shape it into the desired form. This is typically achieved through processes such as turning, milling, and drilling, where tools cut away material from an initial block or piece.

In contrast, additive machining refers to processes that build up material to create a part. This includes techniques like 3D printing, where layers of material are added until the final object is formed. Understanding these two fundamental types of machining is crucial because they represent the distinct methodologies that define how parts are created in manufacturing.

While processes like forging and casting, or specific operations like milling, drilling, turning, and shaping, are important in the context of machining, they fall within the broader categories of subtractive and additive machining. Thus, recognizing these two main types provides a comprehensive framework for understanding the various techniques used in precision machining.