The ElecFreaks micro:bit Breakout Board is a breakout Board compatible with the BBC Micro:bit. The side pins on BBC micro:bit board can lead to the input signal or generate control signals with its special interface. Since the other pins on the micro:bit are too close to each other, this breakout board is an ideal solution to expand its possibilities. As for pins of 0/1/2/3V/GND, you can use alligator clips to connect to the signals.
 
Also, the voltage of micro:bit is 3.3V, while other modules (like LED digital tube modules, IIC LCD modules, etc.) connected to it requires 5V power supply and 5V TTL voltage to work properly. Luckily, this breakout board can then completely match with the BBC Micro:bit pins which means you can connect breakout modules conveniently.