An economy is the production, distribution and trade and consumption of goods and services. The problem in economics is that we have a finite amount of resources, while the potential of human consumption is infinite. This is what every scholar and school of thought is trying to solve. There are many different schools, modern, Marxist, Austrian, Stockholm, Keynesian, etc., but three of them have played the greatest role in shaping the economic thinking and policies we now use in our daily lives: Adam Smith, the Austrians, and the Austrians.
Adam Smith School of thought
Adam Smith is considered the man who laid the foundation for modern capitalism. Before Adam Smith, the production of goods functioned mainly in small villages where people made everything they needed in their daily lives alone and involved in every production stage . Adam Smith argued that the division of labour among workers in their individual subtasks often leads to greater skill and higher productivity in each subtask than would be the case if the same number of workers all performed the original comprehensive task
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Austrian School of thought
The Austrian School rejects the idea that the economy can be understood using mathematical models or quantitative analysis alone. Instead, it focuses on the role of humans action and decision making.
It argues that goods provide a utility and that utility decreases for every extra unit produced .the Austrian School generally advocates for laissez-faire economic policies and limited government intervention in the economy. The school argues that government intervention in the market process can disrupt the natural coordination of economic activity and lead to unintended consequences.
Keynesian School of thought
Keynesian school of economics came and really filled the voids and mistakes the other two schools left. According to Keynesian theory, economic agents, such as consumers and investors, are often uncertain about the future and this uncertainty can cause fluctuations in aggregate demand. Therefore, government policies can help to reduce uncertainty and promote economic stability.
In terms of policy, the Keynesian School generally advocates for government intervention in the economy to promote full employment and stabilize economic activity. Keynesian economists argue that government policies such as deficit spending, tax cuts, and interest rate adjustments can stimulate economic growth and employment. What we saw in the Covid-19 years, the unlimited printing of money with almost unlimited government spending was his school of thought.