1. What (and how much) to produce?
2. How to produce it?
3. For whom to produce?

Depending on the way a society uses as the basis for its economy, four economic systems can be identified:

1. traditional economy;
2. trade economy;
3. command (centrally planned) economy;
4. mixed economy.

A traditional economy is a historical system used in Neolithic Civilisation based on agriculture. The exchange of goods, if any, was on the basis of bartering, i.e. mutual exchange of goods. It was, and is, an underdeveloped economic system which, when change occurs, develops into one of the following currently used systems.

A market economy is based on free enterprises which produce goods for customers and attempt to make as much profit as possible. They rely on two forces which dominate the free market, supply and demand and competition. The law of supply and demand balances the amount and prices of consumer goods whilst competition makes businesses and individuals stretch their abilities to their fullest extent and create a successful economy.

A command economy in contrast is a centrally controlled system where the economy aims to fulfil plans prepared by governments. More attention is paid to industrial goods than consumer ones. This system was actively utilised in socialist countries in Central and East Europe during 20th century.

A mixed economy is widely used in most developed countries where the scale of government activities can significantly differ. Governments often prepare a legal framework for a market economy, provide systems of social security, redistribute income in the form of various allowances and benefits, eliminate some negative effects through regulation or taxation and provide public goods and services such as schools, hospitals, roads, etc.

All the economic systems work to fulfill unlimited people´s wants on one side and to use scarce resources on the other side. From this aspect, economics is defined as a study of choice and scarcity.
Human needs are defined as material items which people need to survive (food, clothing, shelter) while wants are the items people would like to have (special clothes, jewellery, entertainment. All the economic activities aim to fulfil these wants so they are said to be the driving force behind the demand for goods and services.

Human needs and wants can be divided in different ways. The simplest division is basic (food and clothing), cultural (books, theatres, education, etc.) and luxury (car, jewellery, luxury house, etc.).
Other ways of dividing human needs and wants:

• individual and social
• material and immaterial
• essential and non-essential
• biological and cultural
• present and future.