What do you understand by the term 'auto - protolysis' of water? What is its significance?

Explanation:

Auto-protolysis is a self-ionization chemical reaction in which two water molecules react to produce a hydroxide ion and a hydronium ion.

                                       2H2O  H3O+ + OH-

Significance of auto-protolysis of water-

It shows the amphoteric(can act as an acid as well as base) behavior of water.

Final Answer:
As we can see, auto-protolysis is a reaction to produce constituent ions of hydroxide and hydronium.