To accept credit cards online you will need a Merchant Account and a Internet Payment Gateway.
A Merchant Account is basically the same thing as a bank account, except usually it is a temporary storage of your funds until it is deposited into your normal bank account.
An Internet Payment Gateway is the place that does the online transaction. They will verify the credit card of your client, make sure it has funds, and usually do a quick fraud check.
We recommend using Stripe which doesn’t charge any monthly fees or hidden charges and their service combines both the Merchant Account and Internet Payment Gateway. Their rates are very competitive and clearly listed on their website. If you want to use Authorize.net We offer merchant accounts and internet payment gateway accounts via our partner Merchant Focus.