Numeric Control (NC) and Computer Numeric Control (CNC)

1. Numeric Control (NC) :
Numeric Control is a traditional way of establishing an automated control on machining tools.This process is controlled by numbers, letters, symbols.The processes here are controlled by set of instructions which is called as a program.As it is a traditional or naive method, so it has less computational capability.It is less costly and requires less maintenance.
Example:

3D printers, boring tools 

Properties of NC :

1. It is a traditional method of having control over machinery.
2. It provides less flexibility.
3. Instructions are given with the help of punch cards.
4. For changing the functioning, the information on the punch card is modified.
5. It has less computational capability.
6. It cannot run continuously for much time.
7. It is not programmable and considered as hardwired.
8. It is less expensive and has low maintenance.
9. It has high accuracy and more capability.
10. The punch card contains set of instructions.

2. Computer Numeric Control (CNC) :
Computer Numeric Control is a better version of having the control on the machinery which has a microcomputer attached to the machine. The program is written in the form of alphanumeric codes.As this is a better version of control over the machinery it has more computational capabilities. It is more costly and requires high maintenance.
Example:

Lasers, mills 

Properties of CNC :

1. It is a new and better version of having the control on machinery.
2. It provides more flexibility.
3. Instructions are given through the keyboard which is attached to the computer.
4. For changing the functioning, the program on the computer itself is changed.
5. It has more computational capability than NC.
6. It can run continuously even upto 24 hours.
7. It is programmable and is considered as softwired.
8. It is expensive and requires more maintenance.
9. It has low accuracy and less capability.
10. The program is written in alphanumeric codes and is generated by CAD(computer aided design).