What defines a CNC machine in the context of metal cutting?

A CNC machine, or Computer Numerical Control machine, is defined by its ability to be operated and controlled through a computer interface. This means that the movements and operations of the machine are guided by a coded program, which allows for high precision and consistency in metal cutting operations. CNC machines can execute complex cutting paths, manage multiple operations automatically, and maintain tight tolerances with minimal human intervention.

In a comparison to the other options, a manually operated lathe relies on direct human control for its operation, lacking the precision and programmability of CNC systems. A hydraulic press is primarily used for shaping and forming materials rather than cutting them, and it operates based on hydraulic force rather than computerized control. An automated conveyor system is designed for transporting materials, not for performing cutting operations. Therefore, the unique capability of a CNC machine to integrate computer control with machining processes solidifies its definition in the metal cutting context.