Why is the Federal Reserve System of interest?

In talking about the Federal Reserve System of the United
States, it is of interest because it has a huge impact (potentially) on the United
States economy.  This is because of the fact that the Federal Reserve is the central
bank for the United States.

As the central bank for the
country, the Fed can do things like raising and lowering interest rates.  This often
impacts the amount of economic activity that goes on in the country.  The Fed can also
raise and lower the money supply by buying or selling government bonds.  This, too,
affects the level of economic activity in the country.

By
its actions, then, the Fed can have an impact on the economic health of the nation. 
Therefore, it is (or should be) of interest.