Once you turn 18, you may think you are now an adult but be very cautious as the grown-up world is a scary place. You will probably start to receive a lot of junk mail from banks and be tempted from marketing teams to sign up for credit cards, but be careful!
Credit cards are basically a small plastic card issued to users as a method of payment. It allows you to buy goods and services based on a promise that you pay for these goods and services. So in other words, credit cards are basically just a personal expensive loan.
However, not all credit cards are bad. If you are well disciplined and don't let credit card companies rip you off, then you may find having a credit card useful, but I say it again, remember to be very careful.
First of all, when you receive a credit card, it comes with a spending limit, i.e. the amount you are being offered as a loan. Then each month you will receive a statement from the credit card company telling you how much you have spent and where you spent it. You can choose to pay off all the money you owe in one go or just pay some of it. However, if you decide to pay off part of your credit card balance then you will have to pay a minimum payment which you must make. If you can't afford to repay your credit card bill you could quickly fall into debt.