How are the ideas of liberals different from those of conservatives?

Tough question. 
     People can be biased... 

To make things short, liberals are open to new changes happening in the world. Conservatives (conservative means old-fashioned pretty much) on the other hand, are more "traditional". 

Check this site out if you want more- http://www.differencebetween.com/difference-between-liberal-and-conservative/ 

Fiscal policy because it refers to the use of government spending and tax policies to influence macroeconomic conditions, including aggregate demand, employment, inflation, and economic growth.