Those of you who watched college sports last weekend know that one of the most exciting plays in football is a reverse. In a classic example, it happens when the offensive team makes the defense think it is running left, but out of the blue, a runner crosses behind the quarterback, takes the ball and streaks in the opposite direction. The stock market has its reversal plays, too, and they are among the most rare and dramatic of technical patterns -- as we saw in July and October to the upside, and might soon see again this month to the downside. An "outside reversal day" occurs when the high point in the trading of an equity or a broad index exceeds the previous day's high and the low exceeds the previous day's low, and the close is at the bottom or top of the range. Thus, stock charts in which each day's high, low and close prices are drawn in the shape of a vertical bar show that the reversal day's action extends above and below the prior day's action, which is why technical traders call them "outside" bars. If the stock or index was trending down during the weeks prior to the outside bar, then an outside reversal bar that closes at or near the top of the day is considered very bullish. It means that sellers gave it their best shot that day, but were swamped by buying pressure and laid down their arms. Likewise, if the stock or index was trending up during the prior weeks, an outside reversal bar that closes near the bottom of the day is considered very bearish. It means that buyers gave stocks a final hard push, but were overwhelmed by selling pressure.