The Arduino Mega 2560 is a microcontroller board based on the ATmega2560. It has 54 digital
input/output pins (of which 14 can be used as PWM outputs), 16 analog inputs, 4 UARTs (hardware
serial ports), a 16 MHz crystal oscillator, a USB connection, a power jack, an ICSP header, and
a reset button. It contains everything needed to support the microcontroller; simply connect it
to a computer with a USB cable or power it with a AC-to-DC adapter or battery to get started.
The Mega is compatible with most shields designed for the Arduino Duemilanove or Diecimila.