Final answer:
In CNC programming, the term for straight-line movement is linear interpolation, which is crucial for generating precise tool paths in the X, Y, or Z plane.
Step-by-step explanation:
In CNC programming, straight-line movement is called linear interpolation.
This type of motion refers to the scenario where a tool moves along a straight path from one point to another in either the X, Y, or Z plane or any combination of these planes.