Take out a cooled bottle of water from refrigerator and keep it on a table. After some time you notice a puddle of water around it. Why?

The cooled water bottle has a very cold exposed surface. Due to this cool exposed surface, the water vapor in the atmosphere collides with it and condenses into water droplets. The condensed water molecules spread around the bottle. So a puddle of water is noticed after some time. 

As the cooled water bottle is taken out of the refrigerator, it is at a lower temperature than the air outside the refrigerator. This creates a temperature difference. Hence, when the water vapor in the atmosphere collides with the cool bottle, it condenses into water droplets (as it loses heat) and we see water droplets on the outer side of the bottle.

Extra information:

Condensation: The process in which a gas changes into a liquid on cooling is known as condensation. Condensation happens when either the air is cooled to its dew point or it becomes so saturated with water vapor that it cannot hold any more water.