Using the shop anonymously is possible as long as no order is placed via the button "Checkout".
The payment is done via the payment system PayPal. Via PayPal, also paying via credit card without creating a PayPal account is possible.
Your PayPal account or credit card is charged when the order is completed.
The PayPal Acceptable Use Policy is available here: https://www.paypal.com/us/webapps/mpp/ua/acceptableuse-full
The eBooks are delivered as PDF (Portable Document Format) files and can be shown with the free of charge software Adobe Reader.
Adobe is a registered trademark of Adobe Systems Incorporated in the United States and/or other countries.