Economics

Economics is the study of efficient allocation of scarce resources in order to satisfy the unlimited needs and wants.

Types of Resources

• Natural
• Human (labor force)
• Physical (man-made)

Production - making products & services

• What to produce?
• How much to produce?
• To whom to produce?

Factors of Production

1. Land
2. Labor
3. Capital
4. Entreprenuership

Microeconomics

Microeconomics examines the behaviour of basic elements in the economy, including individual agents and markets, their interactions, and the outcomes of interactions. Individual agents may include, for example, households, firms, buyers, and sellers. 

The study of microeconomics involves several "key" areas:

• Law of Demand - a microeconomic law that states, all other factors being equal, as the price of a good or service increases, consumer demand for the good or service will decrease, and vice versa.
• Law of Supply - a microeconomic law that states that, all other factors being equal, as the price of a good or service increases, the quantity of goods or services that suppliers offer will increase, and vice versa.
• Elasticity - the measurement of how responsive an economic variable is to a change in another variable. Elasticity can be quantified as the ratio of the percentage change in one variable to the percentage change in another variable, when the later variable has a causal influence on the former. It is a tool for measuring the responsiveness of a variable, or of the function that determines it, to changes in causative variables in unit-less ways.
• Equilibrium - a state where economic forces such as supply and demand are balanced and in the absence of external influences the (equilibrium) values of economic variables will not change.

Macroeconomics

Macroeconomics analyzes the entire economy (meaning aggregated production, consumption, savings, and investment) and issues affecting it, including unemployment of resources (labour, capital, and land), inflation, economic growth, and the public policies that address these issues (monetary, fiscal, and other policies).

Macroeconomists study aggregated indicators such as:

• GDP (Gross Domestic Product) - one of the primary indicators used to gauge the health of a country's economy. It is the monetary value of all the finished goods and services produced within a country's borders in a specific time period. Though GDP is usually calculated on an annual basis, it can be calculated on a quarterly basis as well.
• GNP (Gross National Product) - a broad measure of a nation's total economic activity. It is an estimate of total value of all the final products and services produced in a given period by the means of production owned by a country's residents plus any income earned by residents from overseas investments minus income earned within the domestic economy by overseas residents.
• CPI (Consumer Price Index) - a measure that examines the weighted average of prices of a basket of consumer goods and services, such as transportation, food and medical care. It is calculated by taking price changes for each item in the predetermined basket of goods and averaging them. Changes in the CPI are used to assess price changes associated with the cost of living; the CPI is one of the most frequently used statistics for identifying periods of inflation or deflation.
• Inflation rate - In economics, inflation is a sustained increase in the general price level of goods and services in an economy over a period of time. When the price level rises, each unit of currency buys fewer goods and services.
• Deflation Rate - In economics, deflation is a decrease in the general price level of goods and services. Deflation occurs when the inflation rate falls below 0% (a negative inflation rate).

Economists

Some influencial economists and thier works/contribution:

1. David Ricardo - Political Economy
2. Thomas Malthus - Population to the Economy
3. Adam Smith - Theory of Price Creation