The Federal Reserve's main tool for managing the economy is to change the federal funds rate, which can affect not only borrowing costs for consumers but also shape broader decisions by companies like how many people to hire. WSJ explains how the Fed manipulates this one rate to guide the entire economy. Illustration: Jacob Reynolds More from the Wall Street Journal: Visit WSJ.com: http://www.wsj.com/ Visit the WSJ Video Center: https://wsj.com/video On Facebook: https://www.facebook.com/pg/wsj/videos/ On Twitter: https://twitter.com/WSJ On Snapchat: https://on.wsj.com/2ratjSM #Fed #InterestRates #WSJ