Gross Domestic Product, or GDP, is the total value of everything produced in a country over a certain time.

It shows how healthy a country’s economy is.

There are three main ways to calculate GDP:

1. Production Approach: This method adds up the value of all final goods and services made in the country. It looks at what is produced at every step.

2. Expenditure Approach: This is the most common way to calculate GDP. It adds up all spending in the economy. The formula is:

   $GDP = C + I + G + (X - M)$

   Here’s what the letters mean:

   • $C$ = Consumer spending (what people buy)
   • $I$ = Investment (money spent on things that will help the economy grow)
   • $G$ = Government spending (money the government spends)
   • $X$ = Exports (goods sold to other countries)
   • $M$ = Imports (goods bought from other countries)

3. Income Approach: This method looks at all the money earned by people in the country. It includes wages (salaries), profits, rents, and taxes, but subtracts any subsidies (money given by the government).

Knowing how GDP is calculated helps us understand what is happening in a country’s economy. It can also help us judge how well a country's economy is doing overall.