Arduino Leonardo

The Arduino Leonardo is a microcontroller board based on the ATmega32u4 that includes  20 digital input/output pins  where  7 can be used as PWM outputs and 12 as analog inputs , a 16 MHz crystal oscillator, a micro USB connection, a power jack, an ICSP header, and a reset button.  We can simply connect it to a computer with a USB cable or power it with a AC-to-DC adapter or battery to operate . The Leonardo has built-in USB communication that eliminating the need for a secondary processor. This allows the Leonardo to appear to a connected computer as a mouse and keyboard.   The drivers are  automatically installed plugging with an USB cable to the   PC. The software  can be found  in the official site .