What is this indicator?
The sequence of higher or lower highs and lows that defines the market's overall trend direction. A break in structure (say, a lower low during an uptrend) is often the first sign of a trend change.
How to read the chart
A pattern forming completely and getting confirmed by volume or the next candle raises the signal's validity; an incomplete or unconfirmed pattern can produce the opposite result.
Practical tip
A pattern's validity increases on higher timeframes and with heavier trading volume; on very low timeframes there's a lot of noise.