The Arduino Micro has a built-in USB port that makes the Micro recognizable as a mouse or keyboard.The Micro is a microcontroller board based on the ATmega32U4, which was developed in cooperation with Adafruit. It has 20 digital input/output pins (7 of which can be used as PWM outputs and 12 as analogueue inputs), a 16 MHz crystal oscillator, a micro USB connection, an ICSP header and a reset button. It contains everything was needed to support the microcontroller; simply connect it to a computer with a micro-USB cable to get started. It has a form factor that makes it easy to place on a breadboard. The Micro-Board is similar to the Arduino Leonardo in that the ATmega32U4 has built-in USB communication, eliminating the need for a second processor. This allows the Micro to appear as a mouse and keyboard to a connected computer, in addition to a virtual (CDC) serial/COM port. It also has other effects on the behavior of the board; these are described in detail on the Getting Started page