A skimmer is a device used by fraudsters to illegally collect information from credit or debit cards. These small gadgets are often placed over card readers at ATMs or gas pumps, capturing card details when unsuspecting users swipe their cards. The stolen information can then be used for unauthorized transactions. To protect against skimming, consumers should regularly check their bank statements for unusual activity and use ATMs located in well-lit, secure areas. Additionally, using RFID-blocking wallets can help safeguard against electronic skimming, where data is stolen wirelessly from contactless cards.