Purified water is usually tap or groundwater which has been treated to remove harmful substances like bacteria, fungi, and parasites.
This means that drinking it is pretty much guaranteed to be safe.
Like distilled water, purified water is a great option if your immediate water source is contaminated.
That said, many countries purify tap water, so you’re basically drinking purified water every time you fill a cup from your kitchen sink.
Because all potentially harmful substances are removed from purified water, you also miss out on some of the potentially beneficial ones that are added to tap water supplies like fluoride, which helps to reduce tooth decay.
In addition, purchasing purified water or even installing a filtration system at home can be pretty costly.