The Breakout gaps occur when the price action is breaking out the trading range. Such Gap is witnessed in the HDFC BANK.
The Characteristics of the Breakout Gap:
1) Breakout gaps occur only when the price gives breakout from the trading range. This is evident from the chart.
2) The Gap may not be filled in the near term. In this example, the gap appeared on 16-Feb-2017 is not yet filled.
3) The Volume during the Gap day should be High. From the example, it is evident.