CartComponent This object is intended to represent a common shopping cart, and contain some of the most common shopping cart operations. Currently discounts are relatively simple. The Discount class will be evolving into more complex discount operations. Discounts can apply to either shipments or items, as flat or percentage, and be calculated before or after tax. Items and Shipments can be taxable or discountable. There are boolean flags in both objects. Tax is configurable. It can be turned on or off, and the rate can be set. These objects are intended to be wrapped by a larger e-commerce system. These objects have the most common variables. For example, a cart can be broken down to just store product ID's, then stored as a string in the database. When a customer returns to your store, they may want to reload their previous shopping cart or wishlists. One of the main features of these objects is the ability to import and export json strings, and be easy to work with.