One person thinks of an object and commits it to memory without telling what it is. The other players take it in turns to ask questions. The person thinking of the object can only reply with the words ‘yes’ or ‘no’.
“Is it an animal?”
“Is it a mammal?”
“Is it a fish?”
And so on until a player thinks they know what the object is. They can take a guess at any point, but if they are wrong they are out of the game. If they are correct, they win and it is their turn to think of an object.