H2O is a simple molecular compound with a tremendous impact on all life. All living things rely on water to live. From tiny cyanobacteria to huge elephants, life needs water to survive. Scientists claim that life first appeared in the ocean, about four billion years ago.

Water makes life possible on Earth. Water cycles from the air to the land, then to the many bodies of water and once again back to the air. Water shapes our planet and affects many aspects of our lives, from the way our body fun...