What goes up but never comes down?

Two boys wish to cross a river. The only way to get to the other side is by boat, but that boat can only take one boy at a time. The boat cannot return on its own, there are no ropes or similar tricks, yet both boys manage to cross using the boat.

How?

Can you solve below mathematical equation?

2^1234 - 2^1233

You can hear me, but you can't touch or see me.

What am I?

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 the riddle which can be asked all day with a different correct answer each time.

You are in a room with no metal objects except for two iron rods. Only one of them is a magnet.
How can you identify which one is a magnet?

Irene killed hundreds of people mercilessly and yet the police were not able to put her behind the bars. Why?

Can you name some countries which do not have the alphabet 'A' in them?

Two trains start at the same time, one from Bangalore to Mysore and the other from Mysore to Bangalore. if they arrive at their destinations one hour and four hours respectively after passing one another, how much faster is one train running than the other?