PayPal has become one of the most popular methods of payment for
ECommerce
shops. It's free, easy to use and osCommerce comes with the code for it installed. But some people were

not happy with it since the customer had to leave the site to make a purchase. PayPal responded to
this need with their PayPal Website Payment package, called PayPal Pro by many. While not free to use,
it does offer full integration into the site. Your customer doesn't even know they are using
PayPal in most cases. And what is better, the cost to use it is less than popular payment gateways
like Authorize.net. In fact, if the shops volume is high, it can even be cheaper than the free PayPal
version due to the different interest rates PayPal charges.