This document discusses the major activities and functions of central banks. It explains that central banks historically served as bankers to governments and had control over money supply through printing currency. Their modern functions include conducting monetary policy to stabilize economic growth and inflation through interest rate adjustments and money supply management. The primary reason for establishing central banks is to ensure control over a country's currency and monetary system. The document also outlines the objectives, design considerations, and fundamental tools of central banks like the European Central Bank.