Do we really know earth?

   The ocean is the lifeblood of Earth, covering more than 70 percent of the planet's surface, driving weather, regulating temperature, and ultimately supporting all living organisms. Yet for all of our reliance on the ocean, 95 percent of this realm remains unexplored, unseen by human eyes. Watch the video below to see nature in the deeps.

I got this info from http://oceanservice.noaa.gov and youtube.