U.S. stocks just finished their best day in more than two years, with the Dow gaining 4% and the Nasdaq gaining 5%. Actually, it may be more accurate to say that U.S. stocks had their best hour, given that the entire rush began after 3pm (after a back-and-forth day that went red after Bernanke’s comments).

Call it a correction. Call it a flash bash. Call it just another reminder that machines, not people, control the equity markets. No matter what, the chart is stunning: