At low volumes, codes can be printed on labels with a desktop printer and applied by hand. As line speed grows, automation becomes necessary.
A typical setup includes: a printer or print-and-apply unit that prints the code on a label and applies it to moving packages automatically; direct printing, which puts the code on the package with a laser or inkjet printer; a camera or verifier scanner that reads every code and rejects poor ones; and software that gets codes from the marking system and keeps track of those printed and verified.
The right choice depends on packaging material, line speed and conditions on the shop floor. BDB will study your production conditions and propose a suitable solution.