On a Web site that sells products or services online, the shopping cart is a common metaphor (from the original grocery store shopping cart) for the catalog or other pages where a user reads and makes selections. Typically, the user checks off any products or services that are being ordered and then, when finished ordering, indicates that and proceeds to a page where the total order is placed and confirmed. The programming that provides a Web site with the ability to build a catalog and its associated database and to integrate pages into its site that provide users the ability to shop is known as shopping cart software.
A primary consideration when choosing shopping cart software is whether it will continue to serve a Web site's needs as its catalog and volume of orders grow.