This website allow merchants to accept credit cards from their customer, so they can send invoices to their customers via emails and let them pay immediately by clicking “pay now” button. See a similar paypal service below:
[url removed, login to view]
This service is much simple that shown in video, as we don't need customer profile, don't need track items, quantities. And we use one currency only.
for more information, please read the attached 2 pages document.