Carding
Carding, or credit card stuffing, is a situation when a carder, which can be a person or a service such as Dumpsandpins or Creditcarddumpswithpin, tries to make small purchases with multiple credit card numbers on different ecommerce platforms. During this time an e-store sees an uptick in payment authorizations from the same user.
Dark web
Carders, for example Bestplacetobuyfullz or Ccshoponline, will extract credit or debit card details using various methods. This data can be found on the dark web. Carders then use these cards to purchase goods from online stores. They stay anonymous and can't be tracked.