Bollinger Bands are a technical analysis tool, specifically they are a type of trading band or envelope . Trading bands and envelopes serve the same purpose, they provide relative definitions of high and low that can be used to create rigorous trading approaches, in pattern. recognition, and for much more.
The uniqueness in these bands is that you can enable the breakout alerts and even change from the basic sma bollinger bands to ema bands. The application of 5 bands is unique to certain strategies.