An intern is someone who is used to complete the hierarchy in any office or corporation.
They are there to do every else's work, usually for no money, as well as any menial task like polishing trashcan pedals. They are also present to be the target of venting and rage, even by the water cooler and coffee maker. For if the two latter items are not happy and running perfectly, there will be hell to pay, even when an intern is not working in the same building where they are.
The whole point of this is to be able to attract the very best psychopaths to run a company. For those bastards just love to hand out abuse and impossible tasks that will just get passed down to the lowest of the low on the food chain, the interns. If by chance the interns do a great job, the psychopaths will step up and take all the credit. If things go wrong, guess who gets the blame. Yes, Michael Eisner, we just might be talking about you.
By the time an unpaid internship is over, a person will be judged ready for the regular corporate life of drudgery and pain, and at low wages besides. Forewarned is forearmed. And four armed is half an octopus.