C

capture

The process of capturing funds from an authorization.

card-not-present transaction

A credit card transaction in which the merchant receives the credit card number but cannot physically link the card to the purchaser. This includes telephone and mail orders, as well as online transactions.

card-present transaction

A situation in which the cardholder (and the card) is physically present at the time of purchase. Card-present transactions account for the majority of credit card transactions in the world and are accounted for by traditional retailers (gas station or restaurant) and all other situations in which the cardholder is present at the time of purchase.

certificate authority

A verifier of the relationship between a public key and its associated identifier. A place you can go to get a digital account ID.

CGI

Common Gateway Interface; a specification for creating programs that accept information acquired through World Wide Web pages and pass it on to other programs, or take information from other programs and make it accessible through World Wide Web pages.

chargeback

The act of taking back funds that have been paid to a merchant for a disputed or improper credit card transaction. The issuer can initiate this procedure 30 days after the settlement.

chargeback period

The number of calendar days in which a member may charge sales back to the merchant, beginning with the day after the date the record is first received by the member or agent and continuing until the end of the day on which it is dispatched as a chargeback item.

chargeback reason code

A two-digit code identifying the specific reason for the chargeback.

check guarantee

A service that guarantees check payment (up to the limit defined for the account), provided that the merchant follows correct procedures in accepting the check. The service determines whether the check writer has previously written delinquent checks. Companies such as TeleCheck provide this type of service.

CIX

Commercial Internet Exchange; an industry organization for Internet Service Providers.

cleartext

Text that has not been encrypted.

clearing

The process of exchanging financial details between an acquirer and an issuer to facilitate posting of a cardholder’s account and reconciliation of a merchant’s settlement position.

client

A computer or system that makes requests for some kind of network service from another computer or system acting as a server.

CommerceNet

One of the first Internet consortiums, set up with partial funding from the U.S. government and the State of California. Member companies include Apple, IBM, Bank of America, Hewlett-Packard, and many other firms from Silicon Valley and beyond.

commercial domain

A commercial node or site on the Internet that is controlled by a for-profit entity. It usually has an address that ends in “com” (http://www.mastercard.com), though overseas sites can have an Internet address that ends with a country code, such as NL for the Netherlands or UK for the United Kingdom.

Common Gateway Interface

An interface program that enables an Internet server to run external programs to perform a specific function. Also referred to as gateways or CGI scripts, these programs generally consist of a set of instructions written in a programming language, such as C or PERL, that processes requests from a browser, executes a program, and formats the results in HTML so they can be displayed in the browser. Gateway scripts often add interactivity to a Web page by enabling users to fill out and submit forms for processing.

confirmation letter

A letter sent by a processor to a merchant on a daily or weekly basis to verify batch deposits.

credit

A transaction type that transfers funds from the merchant’s account back to a customer’s credit card. It is the only way to handle a refund after a transaction has been settled. This type of transaction is usually performed when a product is returned to the merchant. A credit can be performed in the transaction area or through a merchant’s storefront application. Check refunds can only be done via credit card or through a nonelectronic, paper check. A credit can only be issued to an account that has not had a previous authorization.

cracker

An individual who uses computers for criminal pursuits. This term is not yet in general use, but is current among computer professionals and academicians. See also hacker.

cryptanalysis

The study of cryptographic processes with the intent of finding weaknesses sufficient to defeat those processes.

cryptography

The study of mathematical processes useful for keeping data secret by encryption, guaranteeing its provenance, or guaranteeing that its content has been unchanged.