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:
“You’ll never succeed in idealizing hard work. Before you can dig mother earth you’ve got to take off your ideal jacket. The harder a man works, at brute labour, the thinner becomes his idealism, the darker his mind.”
—D.H. (David Herbert)
“By constant dripping, water hollows stone,
A signet-ring from use alone grows thin,
And the curved plowshare by soft earth is worn.”
—Ovid (Publius Ovidius Naso)