A Bullish Engulfing Pattern is a two-candle pattern which is often marked as a change in trend or a reversal in the ongoing trend.

The two candles black and white are placed in such a way that the second candle which is a white candle totally engulfs the body of the first black candlestick. The pattern usually appears in a downtrend.

On the second day, price open lower than the previous day's low but then bulls step in to push prices up. The rally eventually take the price above previous day's high which signifies that bulls are in control.