A lot of us have heard of the term GDP, especially toward the end of official year, but probably don't pay much attention to it. But to economists, businessmen, firms as well as governments, GDP is one of the most important tool used to reflect how a country do not only in economic but also in social and political perspectives. But what is GDP? What are its components? Why is it so important? And if GDP is that important and necessary, why are there still controversies against it?

"GDP or Gross Domestic Product is defined as the total value of final goods and services produced within a country's border during a specific period, usually a year." The phrase "produced within a country's border" distinguishes GDP from other measurements of economy. For example, GNP (Gross National Product) is really close to...