A couple of days back I had to take my son for boating. As me, my wife and my son, sat in the boat, we saw a duck swimming effortlessly on water.
It was so stable and serene, we couldn't but notice its serenity. I pointed to the duck and asked my son to look at the duck. He asked me how the duck was able to stay afloat. I explained to him how the duck paddles below the water, etc.,
As I was explaining I realized how much of effort is going on under the water to make the duck look so serene on top of the water.