Have you ever watched Baywatch? It features David Hasselhoff and Pamela Anderson, 2 life guards at a Miami beach. Imagine you are one of the life guards at point A on the beach (shown below), and a swimmer needs your help at point B. How would you reach the swimmer?
There are obviously 2 choices:
1) Take the shortest distance between A and B. Just run straight and swim straight towards B
2) Run at an angle before swimming perpendicular to the shoreline. This ensures that you swim the least.
Note that you can run faster on land than you can swim in the water.
Which way would you take? Is there a faster way?