RSI is a momentum indicator, however most people seem to be using it to go against the momentum by trying to identify tops/bottoms using it. Its in my opinion the wrong way to be using it. It can be easily used for trend following which seems like a better use for it.
Uptrend - RSI > 60
Downtrend - RSI < 40
Sideways - RSI between 40 and 60
If however not...
A simple yet powerful way to filter out choppy ranges or sideways moves without missing out on good trades
It calculates the %-distance of the price to a moving average so you can ignore buy/sell signals around the center line.
The upper and lower line are thresholds to catch reversals of the trend when the distance to moving average is increasing.