The general public is probably unaware that there are actually six classifications of water based on the FDA's "Standard of Identity". Bottled water or drinking water can fall under one or more of the classifications below:
Spring Water - This is water that comes to the surface naturally. It has to be collected at the spring only, or from an underground aquifer feeding the spring. Bottled water from a spring source is popular with American consumers.
Purified Water - This water has undergone several processes such as deionization, reverse osmosis or distillation. Distilled bottled water is sold in gallon jugs for a variety of household purposes.
Mineral Water - Bottled water in this category is differentiated by mineral elements that are derived from the source. Usually contains not less than 250 parts per million of trace elements of mineral salts or gases. The minerals must be natural and not additives to the bottled water.
Sparkling Bottled Water - As it emerges from the source, sparkling water has carbon dioxide as a property. After treatment, it sometimes needs additional carbon dioxide added to it to replace that which is lost in the treatment process. There are several bottled water terms for sparkling water such as "sparkling spring water", "sparkling drinking water", and "sparkling mineral water."
Artesian Water/Artesian Well Water - The water that is bottled from this source comes from an underground layer of rock or sand on which water accumulates. The water level is usually some distance above the bedrock and is tapped at that point.
Well Water - This type of bottled water is derived from a hole that is bored or drilled into an aquifer.