An extract from Wikipedia (translated from Russian):

"A gap on a technical analysis chart is a significant difference between the close price of the previous time frame (chart element) and open price of the next one. It can be seen in the price chart as a "gap".

On stock and commodities markets, the term "gap" is very often used when the closing price of the previous trading session does not match the opening price of the next trading day (thus forming a gap on a daily chart).

Sometimes, a gap is also a significant difference between the adjacent quotes. This is usually caused by unexpected news when the difference between quotes may be 5 times higher than the standard one or even higher than that. Such a gap is not always represented on the chart as a gap. It may well form an elongated element."

Gap analysis is the core of this Expert Advisor's strategy. This EA will be a great addition to your main trading robot as it opens trades rarely, as a rule, no more than once a week. And since gap serves as one of the most accurate and reliable sources of market price predictions (it is either present or absent), this Expert Advisor will provide stable, although not quite frequent, profits.