This document provides an overview of the banking sector, including definitions of banks, bank regulation and regulators, bank functions and services, and the organizational structure of banks. It defines banks based on their functions as financial intermediaries, the services they offer customers, and legal definitions for regulatory purposes. The document outlines traditional bank services such as deposits, loans, payment services, and more recent services including insurance, investment products, and securities dealing. It also describes various organizational forms of banks such as unit banking, branch banking, bank holding companies, and financial holding companies.