Spring water. You forgot to mention spring water. (... and distilled water isn't water at all. it lacks almost all properties of real water. Specifically, it tastes horribly, as opposed to spring water)
@LeopoldBloom I think scientists shouldn't use ordinary language words to give a chemical substance a name. I would call pure H2O "hydrogen oxide". "Water" is much more than just that. It's a mixture of many things; it contains dissolved molecular oxygen (without which fish could not survive in water), dissolved CO2 (a part of which reacts with hydrogen oxide to form HCO3-), and a variety of ions such as sodium ions, potassium ions, calcium ions, etc. That's water.
It depends on what you intend to use it for. Distilled water is the purest and therefore the only option for chemistry experiments. Hydrating yourself with that will kill you, so it's not an option at all for that. Tap water is fine for cleaning and drinking, but I prefer slightly sparkling water as a refreshment.
@LeopoldBloom hmm, I looked it up and it turns out you're right. As long as you get enough minerals from food, it won't kill you. I've been lied to by my biology and chemistry teachers! 😯 It also doesn't offer any health benefits compared to tap water though, assuming that's safe to drink.
@HannibalAteMeOut It’s very pure distilled or filtered water. It would be fine to drink but it would be expensive. Then again, bottled water isn’t exactly cheap nowadays.