Hard water is water that has high mineral content (in contrast with "soft water").
Hard drinking water is generally not harmful to one's health, but can pose serious problems in industrial settings, where water hardness is monitored to avoid costly breakdowns in boilers, cooling towers, and other equipment that handles water. In domestic settings, hard water is often indicated by a lack of suds formation when soap is agitated in water. Wherever water hardness is a concern, water softening is commonly used to reduce hard water's adverse effects.
Read more about Hard Water: Sources of Hardness, Effects of Hard Water, Measurement
Famous quotes containing the words hard and/or water:
“A strange age of the world this, when empires, kingdoms, and republics come a-begging to a private man’s door, and utter their complaints at his elbow! I cannot take up a newspaper but I find that some wretched government or other, hard pushed and on its last legs, is interceding with me, the reader, to vote for it.”
—Henry David Thoreau (1817–1862)
“The senseless drowned
Have faces nobody would care to see,
But water loves those gradual erasures
Of flesh and shoreline, greenery and glass,”
—Howard Moss (b. 1922)