Merchant Account is just like a current bank account integrated with a payment processor that provide transactions with credit cards and checks. Anyone who want to pay online by credit cards and check should has a merchant account. Online payments need a Card Not Present Merchant Account. Most of merchant accounts are not free. One should pay fees every month and for each transaction. Of cause there are free merchant accounts like PayPal and Google Check Out. These one accounts can be very useful in many cases but they also have some limits for the products that you sell. So before creating an account get a consultation from a web developer in order to chose the most suitable one for your business