Moving Average Convergence Divergence (MACD) shows the difference of two moving averages - EMA12 and EMA26,

and a 9-day EMA of the difference is plotted against it to trigger buy or sell signal.

There are three parameters in MACD:

1. MACD line - the difference between the 12 and 26 period EMA
2. Signal line - the 9 day EMA of the MACD line
3. Histogram - a visual representation of the difference between the MACD line and the signal line

MACD is best use in range-bound market to detect the momentum change and overbought/oversold conditions within a price range.

Applications of MACD:

1. Detect overbought/oversold levels

When the MACD line is far above from the centerline, the market is considered to be in overbought condition; while the MACD line is far below the centerline, the market is deemed to be in oversold condition.

2. Crossovers

When the MACD line crosses above the signal line, a buying signal is generated; while the MACD line crosses below the signal line, a selling signal is generated.

3. Divergences

If the price is moving higher, but the MACD line is moving lower, it signals the weakening of the up-trend or a reversal. If the price is moving lower, but the MACD line is moving higher, it signals the weakening of the downtrend or a reversal.