This is the Arduino Uno bootloader, it gives the arduino all of its abilities and features to enable you to use it. So, this piece is here to save the day if a little accident happened, you can simply replace the old damaged Atmel with this new one.
This chip is a great addition in your DIY projects and you can upload the Arduino bootloader to it and start programming by the Arduino IDE.
The ATmega328P microcontroller is used in the robust board Arduino Uno. This microcontroller has 32KB flash memory, 23 general-purpose I/O lines, three flexible timer/counters with compare modes and a 6-channel 10-bit A/D converter.
Product Code: Atmel328P