1. Expansion of the Acronym: CNC stands for
Computer Numerical Control. It refers to the automated control of machining tools by means of a computer.
2. How it Works: A CNC machine processes a piece of material (metal, plastic, wood, etc.) to meet specifications by following a coded programmed instruction (often called G-code) without a manual operator directly controlling the machining operation. The "Numerical" part refers to the fact that the computer uses coordinates and numbers to determine the exact position of the cutting tool.
3. Evolution from NC: Before CNC, there was NC (Numerical Control), which used hard-wired logic or punched tapes. The addition of the "Computer" allowed for much greater flexibility, as programs can be easily edited, stored, and simulated before any actual cutting takes place.