Your goal is to guess the colour code. Press the buttons on the right of the board to add a pin to the board. Once you have a full five pin row completed it will check the code to see if it's correct. You can see the answer to that on the bottom right. If one of them turns white then that one on the latest code is right. If it's black then that one on the latest code is wrong. Previous rows are not counted as part of the code.