This is a game invented by the character Ross in episode 12 of the fourth season of the TV program Friends. It is the same game as played by the characters on the show and as such does not require any knowledge of the TV series itself.
The players split into two teams – intended to be girls and boys, but this only matters for the bonus questions. Each team takes it in turns to answer yes/no questions about the opposite team in one of four categories: “Fears and Pet Peeves”, “Ancient History”, “Literature” and “It’s all Relative”. This is done by submitting Yes/No cards face down for simultaneous reveal with the correct answer(s) from the other team. Some questions are about one member of the opposite team – in which case all members of the answering team submit a guess – and some questions are of the style “Which of us…?”, in which case the answering team collaborates for a yes/no answer for each member of the opposite team. The goal is to answer the most questions correctly about the other team and have the highest points total at the end of the game.
There is also a bonus round – and here the gender divide does matter, because the game is designed so that the boys are asking the girls questions that are supposedly hard for the girls to answer but that the boys themselves should easily know the answer to, and vice versa (no answers are provided for the bonus questions). The bonus round is timed and each team answers as many questions correctly as they can within the time limit.