The term "Bao Yang Yin" is usually used in the stock market, futures or other financial markets to describe a K-line chart. K-line chart is a tool to show the price trend of securities, futures or foreign exchange market. It represents the price change through a column line, which is divided into two types: positive line and negative line.

The positive line indicates that the closing price is higher than the opening price, which is usually indicated by red or blank; A negative line indicates that the closing price is lower than the opening price, usually in green or black. When a positive line completely contains the previous negative line, we call this form "Yin".

In the stock market, "Bao Yang Yin" is usually regarded as a bullish signal, which may indicate the upward trend of prices. However, it should be noted that the shape of a single K-line cannot completely determine the direction of the market, and traders need to combine other technical indicators and fundamental information to make more accurate judgments.