The pattern of higher highs and higher lows (uptrend) or lower highs and lower lows (downtrend) that defines the directional bias of price movement. A break of market structure occurs when price violates a key swing point, often signaling a potential trend change or continuation.
Example
“A trader noticed Bitcoin's market structure shifted from bullish to bearish when price made a lower low, breaking below the previous swing low and signaling a change of character.”