For different types of machining, metal removal characteristics are not the same, cutting more difficult to have higher cutting fluid requirements. The degree of difficulty in cutting process, from hard to easy order as follows: broaching external broaching - tapping screw machining - hobbing - Drilling - boring - forming cutting thread - high speed low feed cutting thread milling - planing - turning drill (single point tool) - sawing grinding.
The order is not absolute, because the degree of difficulty of the geometry of the tool and the workpiece material changes will change processing.