As you point out, you need to establish credit, particularly if you ever want to purchase a house or get a car loan. Since you've seen how credit can be misused, you're likely to handle a credit card well. A credit card can be very handy if you want to make a large purchase--say a refrigerator--and want to pay it off over several months, or if you don't have cash with you when you need to buy something. To avoid tempting yourself, get a credit card with a small dollar limit, say $500, with no option for going over that limit or for taking a cash loan on your card. Since you're only 21, about $500 is likely about all that a bank will allow you anyway. Everytime you use the card, note down the amount you've spent, and keep a record. Always have a plan for paying off the card, and try to pay it off in full most months, avoiding any interest charges.