When the histogram starts to fall or rise, it means that momentum is changing and can be an early warning signal to watch out for what Vegas describes as equality. Please research his material on line to learn more.
In true TradingView spirit, the author of this script has published it open-source, so traders can understand and verify it. Cheers to the author! You may use it for free, but reuse of this code in a publication is governed by House Rules. You can favorite it to use it on a chart.