Air conditioning
Modern air conditioning emerged from advances in chemistry during the 19th century, and the first large-scale electrical air conditioning was invented and used in 1902 by US inventor Willis Carrier. The introduction of residential air conditioning in the 1920s helped enable the great migration to the Sun Belt in the United States.
Carrier Corporation
Willis Carrier is credited with inventing modern air conditioning in 1902. In 1915, Carrier and six other engineers pooled $32,600 to form the Carrier Engineering Corporation. They purchased their first factory in 1920, in Newark, New Jersey.