Distillation is a metho of separating chemical substances based on differences in their volatilities in a boiling liquid mixture. Distillation usually forms part of a larger chemical process, and is thus referred to as a unit operation.
Trivia about distillation
Not only the oldest, but also the most common method of turning sea water into fresh water
(Cheryl of the Clue Crew stands in front of large tanks containing whiskey in Dublin, Ireland.) The whiskey goes 3 times through this purifying process, the evaporation & collection of a liquid via condensation