The Federal Funds Rate is the interest rate at which banks can lend or borrow overnight funds from each other and from the Federal Reserve. It is the primary tool that the Federal Reserve uses to implement monetary policy in the United States. When the Federal Reserve wants to stimulate economic growth, it will lower the Federal Funds Rate, making borrowing cheaper and encouraging lending and investment. Conversely, when the Federal Reserve wants to slow down economic growth and curb inflation, it will raise the Federal Funds Rate, making borrowing more expensive and slowing down lending and investment. The Federal Funds Rate has a wide-ranging impact on the economy, as it can affect everything from mortgage rates and credit card interest rates to the stock market and the value of the U.S. dollar. As such, changes to the Federal Funds Rate can have a significant impact on the financial well-being of normal Americans.