THE RIDDLE OF THE BOX

You may instinctively recognize that this is a box. It is a closed, passive box that invites opening. Once you open it, the box will become interactive. I'm not giving you any hints. You'll have to figure it out all by your selves. You've had to do that all of your lives anyway, haven't you? Please leave questions and answers. I want to know what's in this box, if anything. I leave it to you to fill the box and therefore fill me in. Thank you for dropping by!