The U.S. is a credit card nation. Every person I know here transacts with a credit card and carry only a few cash in their purse. In this country, credit cards are a convenient form of payment, and a necessity if you are making online purchases. However, you must use it wisely and not spend beyond your means. In order to qualify for a mortgage or car loan, you need to have a good credit history. Your credit card helps you obtain one. If you pay promptly, this will improve your score. How will you know your credit score? One way is to do an online credit report.