It moderates Earth's climate because it absorbs and releases heat slowly. It's called the universal solvent because, given time, it can dissolve anything except a few man-made compounds. Once it reaches 32 degrees, it expands instead and, because of this, floats. Aquatic life would not exist - no life would. Water weighs 62.4 lbs.
Water has very high surface tension.
That's why water bugs can walk on it. Only ammonia absorbs heat better than water. It is the only common substance that exists as a liquid at normal temperatures. It freezes at 32 degrees and boils at 212 degrees F. Human Use Demand for freshwater by humans is expected to double between 1989 and the year 2000. Factories use more water than any other material.