Mastermind is a code-breaking game. Click on one of the spheres on the right side of your screen and place them on the holders on the left side. After placing a sequence of 4 spheres, click OK to validate your turn. For each colored sphere placed on the wrong holder, a tiny black sphere will appear on the right of the row. For each colored sphere placed on the right holder, a tiny white sphere will appear. Good luck cracking the code!