A water molecule is bent in shape, and because oxygen is more electronegative than hydrogen, it carries a partial negative charge while the hydrogen atoms carry partial positive charges, making water a strongly polar molecule.

This polarity allows water molecules to surround and separate the ions or polar molecules of an enormous range of substances — pulling apart ionic lattices like salt, and forming hydrogen bonds with polar molecules like sugars — dissolving far more substances, and in greater amounts, than most other common liquids can. This exceptional dissolving ability is precisely why water has earned the label “universal solvent.”

Water's colourlessness, its abundance on Earth, and its boiling point are all real properties of water, but none of them explain its solvent behaviour — only its polar molecular structure does.