A payday loan is a type of loan that lets you borrow money that you must pay back within a few weeks. The way payday loans work is that you borrow a certain amount of money and then you are required to pay back the amount plus interest on your next payday. So if you need some extra money in a hurry, but don't have enough cash to cover a big expense, like a medical bill, you might choose to get a payday loan instead of waiting until you get your paycheck. The downside of getting a payday loan is that the interest rate is usually quite high, so you will end up paying back much more money than you borrow.