Authorize.net

Authorize.net is a payment gateway service provider that allows merchants to accept credit card and electronic check payments on their website and over an IP (Internet Protocol) connection. The Authorize.net Payment Gateway is available 24/7 for processing online payment transactions.

Authorize.net services require an account, and there may be a service fee for processing credit card payments (depending on the selected payment model). Feel free to check more information on their official site.