In an ARQ mode, what is meant by a NAK response to a transmitted packet?

Automatic Repeat reQuest (ARQ) is an error-control method used in digital communications. When a receiving station gets a packet, it performs a mathematical check to look for errors. If the packet is corrupted or incomplete, the receiver sends a 'NAK' (Negative Acknowledgement) back to the sender. The NAK response specifically tells the transmitting station that the previous packet was bad and requests a retransmission of that exact packet. Conversely, if the packet is received perfectly, the station sends an 'ACK' (Acknowledgement). Distractors mentioning that the file was received correctly apply to a final ACK or file completion signal, not a NAK.