What is the PUK with regard to a cell phone?

Answer by  giecocruz (35)

The PUK or Personal Unblocking Key of a cell phone which was written on a brochure that comes with the SIM card package is used to unlock blocked PIN or Personal Identity Number which identifies you as the rightful user of a that particular SIM card.

Answer by  KarenH (212)

It's the PIN Unblocking Code. When you enter your PIN (Personal Identity Number) incorrectly for three times, the phone gets blocked. To unblock it you need to enter your PUK.