When you buy something with a credit or debit card, retailers swipe the card to process the transaction. Increasingly, those card readers are being swapped out with readers that send your card information to thieves.
Especially in quiet or low-volume retail establishments, swapping is a risk. Scammers find or create an opportunity to grab the shop's card reader and leave a replacement -- an identical model -- behind.
If you shop or work at one of these places, keep an eye out for anybody handling the card readers. Nobody except a technician needs to more than swipe a card and punch in a PIN. Retailers are also advised to put an inconspicuous identifier on card readers so it's easier to tell when it's been swapped out.
BankInfoSecurity.com offers more detail: POS Skimming Scam Stopped.
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