In Dan Starbuck Pelletier’s program, the only kings and pawns in the room move on a black-and-white checkerboard. The playing field that exists outside the room is leveled to make way for the world’s ...

Anyone who’s taken language lessons on the Duolingo app is certainly familiar with the Duolingo owl, Duo. If you skip out on lessons, Duo will ping you — crying! — to come back. Over the past few ...