Credit cards become popularly successful in the 1920s.

Visa was originally called BankAmericard, a card offered by Bank of America in 1958 in California.

78 percent of American households — about 91.1 million — had one or more credit cards at the end of 2008. A year earlier, there were 90.4 million households with cards.

41 percent of college students have a credit card.

Eighty percent of American households have at least one credit card. (Source: cardweb.com)

The average level of debt for a middle-class American family is $9,827 (out-of-pocket medical expenses account for $2,194 of that, on average).