The basic process for getting credit is applying for it, getting approved, borrowing the money, and paying it back. There are both positive and negative aspects of using credit. Using credit builds a good credit history. If a person has never used a credit card or taken out a loan, it is unclear whether he is a good credit risk. By doing this, you are building a credit rating without paying the interest rates.
Credit cards are useful in emergencies.
If the furnace goes out in the middle of winter, and you do not have enough savings to buy a new one, you cannot wait to save up enough money. A credit card allows a person to get the furnace when he needs it and pay it off later. The only problem is that furnace will cost even more because the person has to pay interest. Of course, this is impossible when you get a loan for a house or car. However, if you make a few small purchases during the month with a credit card, and pay off your balance at the end of the month, there will be no interest charged.