For several years I have been using a protective sleeve, in which I put my credit cards and passport, to avoid my personal info from being stolen. There is something called Radio Frequency Identification (RFID) that is a tiny chip in our credit and debit cards. A thief with a card reading device, that looks like a small laptop and costs less than $100 on the internet, can walk by you and automatically read the information off your card.
If your credit or debit card has the symbol of 4 waves )))) or says Pay Pass; Pay Wave; or Blink it has RFID. You can ask your bank if they issue cards without RFID’s.
It is not used just in airports as I initially thought. It could happen while seated at McDonalds or while shopping at Ralphs. It can pick up (steal) the same information from your PASSPORT and school ID’s. A thief can also take a plastic Hotel ROOM KEY and transfer the credit card info onto the room key using that reading device. The thief can then use that room key and swipe it to then charge something.
Instead of a protective sleeve you can wrap aluminum around your card. However the sleeves are so cheap it makes sense to look into this.