You may enter, but you may not come in. I have space, but no room. I have keys, but open no lock. What am I?

A man who was outside in the rain without an umbrella or hat didn’t get a single hair on his head wet. Why?

Baseball bat and ball cost $100. If the bat cost $99 more than the ball, what is the cost of each?

You are trapped in a room with two doors. One leads to certain death and the other leads to freedom. You don't know which is which.
There are two robots guarding the doors. They will let you choose one door but upon doing so you must go through it.
You can, however, ask one robot one question. The problem is one robot always tells the truth, the other always lies and you don't know which is which.
What is the question you ask?

Which country gets ill every time?

Can you find out the missing number in the grid?

On a certain day, John celebrated his birthday. Two days later, his older twin brother Jacob celebrated his birthday.

Is this even possible? How can it be?

Once while in his court, King Akbar asked Birbal to write something on a wall that makes one sad when read in good times and makes one happy when read in sad times.

He took only a few moment and wrote something that fit the requirements. What did he write?

A network of 20 x 10 squares is given to you.

Can you calculate how many unique squares and rectangles can be formed combining two or more individual squares ?

What is black when you buy it, red when you use it, and gray when you throw it away?