Kool-Aid is a flavoured drink mix, owned by Kraft Heinz (yes, the baked bean people).  Basically it's a packet or tub of powder and you mix it with sugar and water, then whack it in the fridge or pour it over ice and you're good to go.  Apparently you can also use the powder as a hair or wool dye (thanks for that suggestion, Wikipedia), but we recommend drinking it like normal people would.