How does credit card payment work?

[jinksys]

I am starting a small business website and need to know the ins and outs of credit card processing from a programming standpoint. What I mean is, once I have the dollar amount they are to be charged...what then? I know that you need a merchant account for processing, but what method do you use to pass the info along?

[Scruffy]

You need the services of a Payment Service Providor (PSP).
They provide the secure server link and process the transaction. Top names are SecPay and WorldPay.

[FalseDawn]

The info you need to pass depends on a few factors, but in all cases there is a minimum required - usually customer name, card info (obviously), and address.

From a programming point of view, different payment gateways might use different methods.

Most will accept a HTTP POST, which is easily accomplished in PHP using cURL - other languages will need different approaches.

authorize.net even provides sample code in a variety of languages:
http://developer.authorize.net/samplecode/

[edited by: lorax at 4:46 pm (utc) on Mar. 8, 2006]
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[Corey Bryant]

You need the merchant account along with an electronic payment gateway (LinkPoint, Verisign's Payflow Services, Protx, Authorizenet.com).

You can also consider using a third party service or 2CO and use their proprietary gateway

-Corey

[puppyhunter]

There are some companies that offer to set you up with merchant account and do the gateway part Such as Optimal Payments and their site even has all the documentation and APIs for most setups.

Have a look at http://www.optimalpayments.co.uk/docsapi.asp

[edited by: lorax at 4:45 pm (utc) on Mar. 8, 2006]
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