About Banking Systems and Security

The questions i've posted is about a very important project i'm doing in order to get a degree of professional in banking business.
I'm not asking to tell me solid answers of what kind of systems and security is used in banks but at least to have some answers and guidance of where to start researching myself this subject because im new to this area of business. Nevertheless if you need any kind of contribution from my part then ask me and i'll do whatever i can to help you.
Regards,
Antonis