In 1902, Willis Carrier was a young engineer working for the Buffalo Forge Company in Buffalo, New York. The company had been hired by a local printing company, Sackett-Wilhelms Lithographic & Publishing Company, to solve a humidity problem in their printing plant. The plant’s paper would expand and contract with changes in humidity, causing the ink to smudge and ruining the prints.

Carrier came up with a solution: he designed a system that would blow air over coils filled with cold water, which would reduce the humidity in the air and keep the paper from expanding and contracting. The system was a success and became the first air conditioning system in history.

Carrier continued to improve upon his design, developing a system that not only controlled humidity, but also temperature and ventilation. He founded the Carrier Engineering Corporation in 1915, which became one of the world’s leading manufacturers of air conditioning systems. Today, air conditioning is an essential part of modern life, making it possible for people to live and work comfortably in a wide range of climates.