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Invents Infinitesimal Calculus
Leibniz discovered calculus in the 1660's, at around the same time as Isaac Newton. They both accused each other of plagurism, but no evidence was ever found to back up either of these claims. -
Credit card idea first used
The concept of using a card for purchases was described in 1887 by Edward Bellamy in his utopian novel Looking Backward. Bellamy used the term credit card eleven times in this novel, although this referred to a card for spending a citizen's dividend rather than borrowing. -
Modern credit card first invented
In 1949, Frank X McNamara, head of the Hamilton Credit Corporation, went out to eat with Alfred Bloomingdale. One of McNamara's customers had borrowed some money but was unable to pay it back. At the end of the meal with his two friends, McNamara reached into his pocket for his wallet so that he could pay for the meal (in cash), but he had forgotten his wallet. Merging the two concepts from that dinner, the lending of credit cards and not having cash on hand to pay for the meal, McNamara came u -
Modern use of Calculus
Credit card companies use calculus to set the minimum payments due on credit card statements at the exact time the statement is processed by considering multiple variables such as changing interest rates and a fluctuating available balance.
