For the controller of micro: bit is small, it’s difficult for beginner to build circuits. The BBC micro: bit has a selection of pins that are located on the bottom edge of its PCB, with this board, you can use these pins to connect additional components to the BBC micro: bit. There is a small bread board on the board, which make it easy to build circuit on the board.
This expansion board provides a fantastic way of learning how to construct and control electronic circuits with BBC micro: bit.