Bollinger Bands Indicator

Bollinger Bands are three lines plotted on a chart. The middle line is a moving average, and the outer bands show volatility. When prices touch the upper band, the stock may be overbought, and if it touches the lower band, it may be oversold.

When price moves close to the upper band, some traders watch for a reversal or book partial profits. If the price hits the lower band, they watch for signs of support or a bounce. A sudden expansion in the bands often signals a big move coming.

If Tata Motors is trading near its lower Bollinger Band and the bands are wide, you might expect a bounce-back or some relief rally. If the bands suddenly widen, a breakout move may be on the cards.

Parameter	Description	Default Value
Standard Deviation	The number of deviations for both bands	2
Window	Number of periods for the indicator	20