Web-based applications: Shopping carts - "What is a shopping cart? Well, a shopping cart is a piece of software that sits in the cgi-bin of your webserver (if it's perl-based) or it sits in some other directory if it uses php, for example. But wherever this software lives, what it does is the same. It takes orders. It presents your products to people on the internet. It lets you know who ordered what so that you can manually run their credit card and make the shipment. Or it automatically connects to your credit card processor through what is called a "payment gateway" and the money goes into your bank account automatically - some shopping carts support payment gateways because their developers realize you want your money fast." [Machineofthemonth.org]