Trading stamps are small paper coupon

Coupon

In marketing, a coupon is a ticket or document that can be exchanged for a financial discount or rebate when purchasing a product. Customarily, coupons are issued by manufacturers of consumer packaged goods or by retailers, to be used in retail stores as a part of sales promotions...

s given to customers by merchants in loyalty marketing

Loyalty marketing

Loyalty marketing is an approach to marketing, based on strategic management, in which a company focuses on growing and retaining existing customers through incentives...

 programs that predate the modern loyalty card. These stamps had no value individually, but when a customer accumulated a number of them, they could be exchanged with the trading stamp company (usually a third-party issuer of the stamps) for premiums

Premium (marketing)

Premiums are promotional items—toys, collectables, souvenirs and household products—that are linked to a product, and often require box tops, tokens or proofs of purchase to acquire. The consumer generally has to pay at least the shipping and handling costs to receive the premium...

, such as toys, personal items, housewares, furniture and appliances.

The practice started in the 1890s, at first given only to customers who paid for purchases in cash

Cash

In common language cash refers to money in the physical form of currency, such as banknotes and coins.In bookkeeping and finance, cash refers to current assets comprising currency or currency equivalents that can be accessed immediately or near-immediately...

, to reward those who did not purchase on credit

Credit (finance)

Credit is the trust which allows one party to provide resources to another party where that second party does not reimburse the first party immediately , but instead arranges either to repay or return those resources at a later date. The resources provided may be financial Credit is the trust...

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