UPDATE 6-25-18: Go to gas stations with new pumps. Why? See Brian Krebs article here. (But still never use your debit card & PIN.)
What is a skimmer?
See if you can guess. Here's an interesting video of a trio of guys (yes, all three are involved) installing a skimmer over a convenience store payment scanner. Two men provide distraction for the clerk and other patrons while the third does the skimmer install. You'll be surprised how fast it goes!
A skimmer is a thing that skims your credit card info from your card without you knowing it. How? Sometimes it sits on top of the real card reader, and look just like it. Hiding in plain site, it skims info from your card when you swipe it.
Here's another video of someone who discovered a skimmer & PIN camera set on an ATM in a McDonalds. Both pieces were designed to look just like the parts of the ATM they were set over.
What about cards with chips - do skimmers work on those? Sometimes...
In the videos above, the skimmers are reading the card info from the magnetic strip when it's swiped. Banks want to phase out magnetic swipes for that reason, and that's why they've switched to chips. The chip connection requires the card to stay in the reader and create an encrypted connection.
Sounds like skimmers are a thing of the past, right? Well...
Magnetic strip tech is still used almost everywhere - especially at gas pumps. If you still use your chip-enabled card in a magnetic strip scanner, then you are using it in places where skimmers could sneak in. It's not easy to spot a skimmer, but like the second video above shows, it can be done. Don't be afraid to wiggle where your card goes in, and look carefully for anything sticky around the edges.
But chip readers are now being compromised, too, and it's harder to see.
What is a shimmer?
A shimmer is a very thing insert put inside the card reader that reads info from the card. See what a shimmer looks like in this video about a shimmer found in a bank ATM in Colorado:
So what can you do to protect your card info?
GAS STATIONS: Use Bluetooth on your phone to detect possible skimmers & shimmers
Here is our own Texas Agriculture Commissioner encouraging folks to use your phone to check for bluetooth-enabled skimmers. We at Technogizmo would add an extra recommendation - forget if the device name looks suspicious or not. If you see any device you don't recognize as yours when you scan with bluetooth, don't connect and turn your bluetooth off.
ATMS: Use your bank's ATM, or use an ATM inside a bank
Using your own bank's ATM should (hopefully) give you better recourse if your info is stolen in one of their compromised machines. ATMs located inside banks usually have hi-def video systems, which reduces those machines as attractive targets.
OR, skip the ATM and go through your bank's drive through or walk inside. You, your info, and your money are most protected when you are inside the bank.
STORES: If possible, never use your debit card. Use a credit card or cash.
Some of us here at Technogizmo really don't like credit cards, so this advice comes with mixed feelings. However, one good thing about credit cards is that they come with more protection against fraud and theft than debit cards do. If you use your debit card to shop, check with your bank to see what kind of protections you have if someone steals money from your account. Will you get it back from the bank? How fast?
Cash is pretty unhackable, but it's not risk free. It can be stolen other ways, especially around ATMs. Here is a great list of ATM safety tips from the Dallas Police Department.