Because of the added risk that the bank has to take when loaning you money that they can’t guarantee you will pay back, they use a system called a credit score to measure your creditworthiness. Essentially, a credit score measures how likely you are to pay back the money you borrow, and can range from 300 to 850.
Source: Equifax
Overall, credit cards offer convenience and can be useful in emergencies, but they require responsible use to avoid high interest rates and the potential for cycles of debt.