A technical indicator developed by Gerald Appel that follows the difference between a series of moving averages. The indicator has two lines, the MACD line and a signal line. A buy signal is generated when the MACD line rises above the signal line. A sell is generated when the MACD line falls below the signal. Because the MACD is generated from moving averages, it has a unique ability to capture wide-swinging moves in markets. Divergence, trendlines, and support can also be applied to the MACD to generate additional signals.