Card personalisation
The step where an anonymous blank turns into somebody's payment card, complete with name, number and its own cryptographic keys.
It starts with data preparation. The issuer sends a file of cardholders and account numbers, and an HSM derives each card's keys from the issuer's master keys. The blanks then run through a personalisation line that prints or embosses the name and number, encodes the magstripe, and writes application data and keys to the chip. For EMV cards, EMV CPS defines how the chip gets loaded, so the same data works whichever manufacturer's card is in the machine.
Most of the work is done by card bureaus such as Idemia, Thales and Giesecke+Devrient, under PCI's card production rules. The PIN mailer goes out separately and usually on a different day, so whoever steals one envelope does not get both. Some banks print cards in the branch with instant issuance, which moves a slice of the factory into a cupboard behind the counter.