Paypal API

Paypal offers a quick and secure way for consumers without having to enter their personal information into each website they want to make purchases from. Even though you can shop at thousands of websites using Paypal, you get redirected to Paypal to log in and complete your purchase. Finally though Paypal has offered a set of API's to developers so that Paypal can be integrated in the the actual website to make purchases.

E - Commerce Times reported the president of Paypal as saying "The whole world is going digital, and the future of how we communicate, how we get information, and even how we transact is in the hands of developers". This is probably the motivation behind what Paypal is offering through their API's. They will be offering automatic currency conversion, parallel payments, and service for users who don't have PayPal accounts.
The API uses SOAP and REST and they even offer sample codes as well as an integration wizard to help you create code for certain API capabilities on their developer website called Paypal X. If you need more information on the development of Paypal services visit their website.

One last interesting thing that Paypal offers is their testing sandbox. The PayPal Sandbox is a way for you to test your code before you implement it into your own website. It is a duplicate of the live PayPal site without actually exchanging any money. The Sandbox allows you to test your entire integration before submitting transactions to the live PayPal environment.