What is the different between classic and keynesian macroeconomics?

Classical Theory: Government has minimal role in the economy, and the macro-economy is self adjusting; meaning consumers and businesses will correct any problems with the economy automatically over time. Classical theory focuses on long-term goals.

Keynesian Theory: Government has a large role in the economy, and focuses on short-term goals. Used mostly in times of recession, government spending is a good way to put money back into the GDP and in turn increase unemployment.