What are the differences between distilled water and rainwater in terms of their purity and composition?

Distilled water is purer than rainwater because it has been boiled and condensed to remove impurities. Rainwater, on the other hand, can contain pollutants and particles from the atmosphere. In terms of composition, distilled water is essentially pure H2O, while rainwater may contain minerals and other substances picked up as it falls through the air.