Credit cards are double-edged swords. They can help you make ends meet as well as get things you want but don't quite have the money to pay for outright. When their balances are kept low and paid off quickly, they pose no problem for most users. But they also come with a risk. Their balances are easy to run up, meaning it's easy to put more on them than you plan. And their payments can be hard to make if something unexpected. When that occurs, things can spiral out of control easily.