What is ozonolysis? What is its significance?

and hydrolysis are collectively called ozonolysis.

Significance: Ozonolysis is quite useful to locate the position of the double bond in an unknown alkene. This is done as shown below:

(i) Write the structures of the products (aldehydes or ketones or both) with carbonyl groups facing each other.
(ii) Remove oxygen atoms from carbonyl carbon and connect them by a double bond. For example, suppose the products of ozonolysis are ethanal and propanone.