Arduino Open-Source Single Board Computer Boards - Arduino A000057, The Arduino Leonardo is a microcontroller board that is based upon the ATmega32u4 microcontroller.
It has everything required to support the microcontroller and to get started simply connect to a computer.
The Leonardo differs from all preceding boards in that the ATmega32u4 has built-in USB communication which eliminates the requirement for a secondary processor.
This enable the board to appear to a computer as both a mouse and a keyboard, in addition to a virtual serial/COM port.
This version of the board comes pre-fitted with headers.
Arduino Leonardo With Headers A000057 Board