Paypal Pro Direct Payment in ASP: This is for direct payment API cliking the link will prompt you the information page where you have to fill your cradit card and billing information , you can cancel by clicking on cancel if you want , once you have clicked the pay by paypal it will check your provided information and you transaction will success or fail according to information provided Paypal Pro Express Check out in ASP: This is a three step process , same by clicking on the express checkout it will prompt you to the new page where you have to provide amount for which you are going to pay for. clicking pay by paypal u will be prompted to pay pal site after ensuring you want to make transaction you will be sent back to own site where you once again asked for making transaction here if you click pay now you transaction will be done else you will be sent back to home page.