Quantitative Easing

When cutting interest rates isn't enough, a central bank can create new money and use it to buy large amounts of government bonds and other assets. That pushes cash into the financial system, lowers longer-term borrowing costs, and is meant to encourage lending and spending when the usual rate tools have run out of room. It's the policy behind headlines like "the Fed's balance sheet just hit a record high." The reverse, selling those assets back off or letting them mature without replacing them, is called quantitative tightening, and it does roughly the opposite.