The Federal Reserve Board is the central bank of the United States. Its name is often shortened to “The Fed.” Its importance to credit cards is that the Federal Reserve Board sets a benchmark interest rate, the federal fund rate. Most credit card issuers offer variable rate cards that peg their cards’ rates to the prime rate. The prime rate, in turn, moves in lock step with the federal funds rate. If the Fed raises the federal funds rate, that raises the prime rate, and most consumers’ credit card rates go up, too.