Bottled water products are normally categorized according to the source of the water and the method that the bottler uses to treat it. The following are common types of bottled water:
Artesian: Water that originates from a confined aquifer, where the water level stands at some height above the top of the aquifer.
Fluoridated: Water that contains fluoride added within the limitations established by the Food and Drug Administration.
Mineral: Water that contains at least 250 parts per million total dissolved solids (TDS). It comes from a source tapped at one or more bore holes or a spring, and originates from a geologically and physically protected underground water source. Bottlers may not add minerals to this water.
Purified: Water that has been produced by distillation, deionization, reverse osmosis, or other suitable processes. Purified water may also be referred to as "demineralized water."
Sparkling: Water that contains the same amount of carbon dioxide that it had at emergence from the source. The carbon dioxide may be removed and replenished after treatment.
Spring: Water that flows naturally to the earth's surface from an underground formation.
NSF International provides information about the different types of bottled water at www.nsf.org/consumer/bottled_water/bw_types.asp?program=BottledWat.