The international card companies have set up some security standards that apply to all card payments. The standard deals with rules for the environment (payment terminal/ payment solutions/ systems/ network) where the merchants and their service provider/ processor handle and store card data.
As a merchant accepting payment cards, you are responsible for ensuring that everyone handling card data complies with the security PCI DSS consists of. The payment terminals and/or the payment solution must be certified, and PA DSS and PCI PED approved in order for the merchant to comply with the requirements. Read more about PA DSS and PCI PTS.
PCI DSS describes the requirements that apply for all merchants transmitting, handling or storing card data. The standard applies for Visa, Mastercard, American Express, Diners, Discover, JCB and Dankort (in Denmark). PCI DSS security standard can be circumscribed to the 12 requirements below: