What is the difference between NANO atmega328P-MCU and atmega328P-AU?

Hey guys What is the difference between NANO atmega328P-MCU and atmega328P-AU?

One is a development board with an ATMega328 and some associated circuity, the other is a standalone microcontroller.

Nothing, microchip just changed the marking scheme to match their marking system in the wake of their acquisition of Atmel

So, they are the same, only hardware placement changed?