A carder is a special kind of criminal that specializes in stealing information about credit cards. Some know many things about digital security and know how to break these "secure systems". Many of these techniques involve obtaining access to administration panels, so that they can steal all of the credit card information off a website. Most, however, buy pre-stolen numbers from vendors and make use of them. Most carders generally do not know much about the technology that they use to commit their crimes.

The primary method that carders use to make money is to use information skimmed off from credit cards to encode the magnetic stripes of their replica credit cards with and make purchases with them.

"Carding" (stealing credit card numbers from the Internet) is a criminal offense.