1.1 Introduction

Human beings require different types of goods and services to satisfy their needs. To earn these goods and services they engage in different activities. These activities bring in their income. Their income determines their standard of living. Large amount of goods and services are required to maintain a higher standard of living. Thus people continuously engage in activities to raise their income levels to achieve higher standard of living. Thus some engage in farming, some in trading and some others in providing services. The purpose all these activities is to earn income for meeting their needs.