It is said that one day in 1950s, Frank McNamara, an American businessman, entertained guests in a restaurant in new york. After eating, he found that he forgot his wallet and had to call his wife to bring cash to the restaurant. He was deeply embarrassed, so McNamara came up with the idea of establishing a credit card company. 1 In the spring of 950, McNamara and his friend Schneider jointly invested110,000 US dollars to set up the Diners Club, the predecessor of Diners Credit Card Company, in new york. Diners' Club provides members with a card that can prove their identity and ability to pay. With this card, members can spend money in 27 designated restaurants without paying cash. This is the earliest credit card. This kind of credit card, which does not need to be handled by a bank, belongs to commercial credit card.