The Contemporary Japanese Financial System
The financial system has many actors, including companies, banks, and governments. This page describes them.
Banks
Banks can be classified to commercial ones and investment ones.
This page uses a comparsion easy for me.
Commercial Banks
Role: storage servers
Power: interest
I/O: deposit/loans
Networking: transactions
Investment Banks
Role: balancer
Power: the margin of the transactions, divend, interest and payback
I/O: selling/buying stock/securities
Networking: networks centralized with stock/securities exchanges