system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why does the Fed adjust the funds rate, and what does it typically mean/signal for the economy?
gpt
The Fed Funds Rate is the primary -- and easiest -- "tuning knob" which the Fed can use to try to influence the economy.

Raising it means that they are worried more about inflation than they are unemployment and economic growth.  

Lowering it means they are worried more about unemployment and economic growth than they are inflation.

Normally these adjustment are small and highly telegraphed (they don't like investors to ever be surprised!).  They become newsworthy when they think that they are worried about inflation so much that they might actually trigger a minor recession with their rate hike... or if they end up lowering the rate super low to near zero.  Once the rate gets to zero the Fed is "out of bullets" and extraordinary measures might be needed the next time around.