In this chapter, you learn how to handle inputs and outputs with micro:bit through the edge connector. The 21 I/O pins can be used to work with analog, digital, I2C, SPI, and UART. Some I/O pins are also specialized to build touch-sensitive applications. The micro:bit only exposes three I/O pins through the edge connector for basic users. If you want to access the full set of I/O pins, you can use the edge connector breakout board.