The #看懂K线 line chart originated in the 18th century in Japan's rice market transactions, initially used to represent rice price fluctuations. It was later improved by American scholars and applied to the stock market, known as the "candlestick chart." Each K line consists of four parts: opening price, closing price, highest price, and lowest price. It reflects price volatility through the body (the difference between opening and closing prices) and the upper and lower shadows (the portions where the highest and lowest prices exceed the opening/closing prices).