The most popular way for accepting credit cards securely over the Net is the secure sockets layer (SSL) protocol. Whether you gather customer credit card information from a form or a shopping cart, you will want it to happen on a secure server. In order to make a server secure using SSL, a digital certificate is required. The digital certificate identifies you as a legitimate business and allows all information to be encrypted for travel over the web.

Merchant Account
For accepting credit cards you need a special bank account. Most banks offer merchant accounts. The price is usually a percentage of each credit card order that you submit. Most banks charge higher fees for risky accounts, such as those with large numbers of charge-backs or fraudulent charges. Usually a U.S. business checking account and good credit are required to get approved for a merchant account for accepting credit cards.

Processing Credit Cards
Dozens of companies offer transaction processing software that sends the right information to everyone involved in the sale — your bank, the customer's bank, the bank issuing the credit card and so on. Some processors lease their services to you for a monthly fee, while others take a percentage of your sales. Some processors will help you get a merchant account if you need one, and many have deals with ISPs that provide everything you need to build an online store. if you plan to do real-time processing then be sure before you make any commitments that your processor is compatible with your merchant bank and your shopping cart software.