What exactly is a short sale?

How do you get a bank to agree to one? Is it more likely to get that than a Deed In Lieu of Foreclosure, for instance?

Do you end up owing any money if it doesn't sell for what is left on the loan?

I guess I don't understand why so many banks are reluctant to do a DIL, but seem more willing (at least, from what I've read) to do a short sale.

If a person's hours aren't producing enough money and they're struggling with payments, will the bank do a DIL? If so, how long do you have to get out?
Added (1). What are the chances of Chase mortgage issuing a deficiency balance waiver in either a DIL or short sale?

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