You probably discovered long ago that credit card companies aren't exactly friendly.

As the credit card business becomes more competitive, card companies are reducing basic interest rates (at least at the start) and making up for them by getting creative about how they separate you from your wallet. Here are some things to be aware of:

* Late charges: Whatever you do, make the check for a credit card bill as soon as it arrives. Companies are squeezing the grace periods ever smaller. Further, they may not credit your payment for days after it arrives. If that means it's late, you'll have a $29 late fee on your next bill.

* Over-limit charges: If your check is credited later than it should be, or if the $29 late fee puts you over your credit limit, you could be charged a $29 over-limit fee.

* Unauthorized charges: One credit card issuer automatically added $7.50 per month for credit insurance to each account. It was up to the customer to cancel it. Another offered a 'free' credit report, but thereafter customers were billed $59 for a three-year credit report service. When customers called the card company, they were referred to a credit reporting company and had to call them for a cancellation number. Then the customer had to call the card company again to report the number and get the charge removed.

* Convenience checks and account transfers. The card company offers a low rate to transfer accounts from other companies. When they do, however, some will add 3 percent of that amount to your bill as their fee.

* Other charges: They may include a charge for not using your card or for calling customer service.

* Raising basic rates: Some card companies scan your credit each month. If you are late with another company, they make a big increase in your interest rate. Self defense: