This is an overlay indicator which uses the classic period settings and signals from the MACD (Moving Average Convergence/Divergence) indicator to overlay a heatmap using all the information the MACD generates with its three periods (12,26,9).
The first two moving averages which the MACD uses (12 and 26) can be plotted on the chart like usual EMAs.
In addition to the background color function (the heatmap) and the EMAs, there is an optional bar color alert when the uptrend or the downtrend as measured by the MACD appears to be very strong.