Many have heard it, but nobody has ever seen it, and it will not speak back until spoken to. What is it?

What can go up a chimney down, but can’t go down a chimney up?

An equation has been laid down using a few matchsticks. However, as you can see, the equation is not correct. Can you correct the equation if you are allowed to add or remove 5 matchsticks?

What is a word made up of 4 letters, yet is also made up of 3. Sometimes is written with 9 letters, and then with 4. Rarely consists of 6, and never is written with 5.

Why Aeroplane windows are round?

Why is it very easy to weigh a fish?

If six children and two dogs were under an umbrella, how come none of them got wet?

Can you place six X (crosses) in below board without making three in a row in any way ?

Nodes are shown below and you need to connect them based on the following rule: Every node can be connected to the number of nodes inside them, i.e. the first node there is a value of 1 which indicates that the first node can connect to exactly one node only.Can you do it?

If you go to the movies and you're paying, is it cheaper to take one friend to the movies twice, or two friends to the movies at the same time?