Hello, I have an idea of developing internet payment gateway similar to PayPal or Webmoney. Since i'm only sophomore at Computer Science, and i've only taken intermediate programming classes, i've no idea where to search for general information about this topic. I do understand that this kind of project is CLEARLY too much to handle for sophomore. Since, it's forum for Pro Webmasters, and probably some of you can point direction of study.

1. What book/source/article would you suggest to read to understand fundamentals of internet payment?
2. What book/source/article would you suggest to read to understand fundamentals internet security?
3. What language is most commonly used for developing payment security of website?

I appreciate any help. Thank you.