In many European countries as well as some others, you may find it difficult to use your credit cards in some places. Especially kiosks you might find at train and subway stations. Companies want credit cards with “chip and pins.” Unfortunately those cards are not yet available here in the States. Mastercard and Visa say they will start offering the chip and pin cards to the U.S. market in the near future, hopefully some time in 2013.
But for now, if you will be in Europe make sure you take a little extra cash with you just in case you find yourself trying to pay for something with a credit card that is no longer accepted. Try to pay for as much as you can before you leave home or confirm with as many places and businesses as possible that there won’t be a problem with using your card.