the idea to help sell breakfast cereals and other products. Today, more than 700 corporations offer coupon discounts. Each year, coupons generate more than 8 billion dollars in transactions within the U.S. alone. Another type of loyalty incentive is the trading stamp. It is distinct from a coupon in that a coupon is redeemable for a specific product or class of product, where as a trading stamp acts like a currency, or a token economy.

It was used as a temporary currency for some former Soviet countries, especially Moldova, and Ukraine after they became independent. There are also internet sites that have coupons that can be used online. Online retailers usually refer to Internet coupons as coupon codes, promotional codes, promotion codes, discount codes, key codes, promo codes, shopping codes, voucher codes or source codes. Internet coupons typically provide for reduced or no cost shipping, a specific dollar or percentage discount, or some other special offer to encourage consumers to purchase specific products or to purchase from specific retailers.

Consumers are individuals or households that consume goods and services generated within the economy. Since this includes just about everyone, the term is a political term as much as an economic term when it is used in everyday speech. Typically when businesspeople and economists talk of consumers they are talking about person as consumer, an aggregated commodity item with little individuality other than that expressed in the buy or not buys decision. However there is a trend in marketing to individualize the concept. Instead of generating broad demographic profile and psychographic profiles of market segments, marketers are engaging in personalized marketing, permission marketing, and mass customization.

A consumer is assumed to have a budget which can be spent on a range of goods and services available on the market. Under the assumption of rationality, the budget allocation is chosen according to the preference of the consumer, in other words, to maximize his or her utility function. In time series models of consumer behavior, the consumer may also invest a proportion of their budget in order to gain a greater budget in future periods. This investment choice may include either fixed rate interest or risk bearing securities.