What is the purpose of an ac coil?

Hi: Pretty much to put it in as simple as perspective as I can is to just say an A.C. ( Air Conditioning Coil ) < notice------ not cooling nor heating , but Conditioning coil, Conditions the air in which you are trying to prep for one reason or another. To dehumidify it, humidify it, heat it, cool it, clean it, on and on and on. Is there more that I can say? Hope this Helps: Jimiwane