What is fiscal policy?

What are the two main tools of fiscal policy?

Would you be able to go into detail about the impact of expansionary fiscal policy and more specifically the fiscal policy used during the Great Recession of 2007-2009 on the economy and business.

I am curious to see if there are any resemblances on how we recovered from the great depression and the differences that we may have possibly learned from. Thank you in advance, just curious to compare my notes.