Put simply, a credit card provides a short-term loan from a bank
that you are expected to repay quickly. In exchange for giving
you a short-term loan, the bank will charge you interest — often
referred to as an Annual Percentage Rate or APR. An issuing bank
will evaluate your credit-worthiness and determine if you are a
low risk candidate (likely to repay) or a high risk candidate
(unlikely to repay) for a line of credit, and will offer you an
APR based on your credit report and how it profiles you
financially. Some banks will offer you a “Teaser” APR —
essentially a low introductory rate that will change to a higher
APR six or more months later. We'll provide some guidance about
this concept below.