Air conditioning units actually condition the air.

I grew up in a house that had an air conditioning unit and an evaporative cooler (we called it a swamp cooler). Swamp coolers are awesome when you live in dry place. Only when the humidity gets too high you need to switch over to the AC. Swamp coolers are cheaper to run so cue arguments on trying to get my parents to switch to the AC when it starts getting humid. 😆