BIG LIFT: Stocks soared Wednesday after the world's leading central banks acted to reduce banks' borrowing costs. The central banks of Europe, the U.S. and others reduced the cost to banks of borrowing dollars.
WHY IT MATTERS: Markets have been rattled by concerns about banks that hold large amounts of debt issued by European governments. As a result, those banks have had trouble accessing the dollars they need to fund their daily operations. Many fear a default by a European country could topple one or more banks. The central banks' action removes some of that pressure.
THE DOW: The Dow Jones industrial average leaped 490 points, its biggest daily gain since March 23, 2009. That was the month that stocks started rising from their lowest levels in 12 years.