Left-side buying refers to buying stocks on the left side of the lowest price point, meaning buying before the lowest point becomes apparent; left-side selling refers to selling stocks on the left side of the highest price point, meaning selling before the highest point appears. The core idea of left-side trading is to predict stock price trends.

Conversely, right-side buying refers to buying stocks on the right side of the lowest price point, meaning buying after the lowest point has appeared; right-side selling refers to selling stocks on the right side of the highest price point, meaning selling after the highest point has appeared.