Conundrums and Brain-Twisters

Classic Conundrums

Which has a winner?
What has four letters?
What is as light as something heavier than air?

Brain-Twisters

What can you catch but never throw?
What has keys but not a lock?
What is black and white and red all over?

Conundrums and Brain-Twisters is a place where you can come to test your wit, or lack thereof.