K-line refers to the K-line chart in the stock trend, which originated from the Tokugawa shogunate era in Japan (1603~ 1867). It was used by merchants in rice market at that time to record the market and price fluctuation of rice market, and was first introduced into futures because of its ingenious and unique plotting method. Many people think that the K-line started from the stock market. Through the K-line chart, you can completely record the situation and performance of the stock market every day or at a certain time. After a period of trading, the stock price forms a special region or form on the chart, and different forms show different meanings. The three K-line combinations of insertion line, holding line and favorable stimulation line are the most common classic bottoming forms.

The Japanese "K" is not written as "K", but as "Ku" (Japanese pronunciation reading kei), and the K line is the pronunciation of "Ku line". K-line diagram is called "Ku-line", and the first English letter "K" is literally translated into "K-line" in the west, which develops from it.

K-line, also known as Yin-Yang candle, is said to have originated from the rice market in Japan in the18th century. At that time, Japanese rice merchants expressed the change of rice price and then introduced it into the securities market, which became the theory of stock technical analysis. K-line is a columnar line, which consists of shadow lines and entities. The hatched part above the entity is called the upper hatched line and the lower hatched line. Entities are divided into positive and negative lines. Among them, the shadow line represents the highest and lowest price of the day's transaction, and the entity represents the opening price and closing price of the day [3].

K-line, also known as candle chart, daily line, yin-yang line, bar line, etc. At present, it is commonly used as the "K-line", which originated from the rice market transactions in Japan18th century Tokugawa Shogunate (1603 ~ 1867) and is used to calculate the daily rise and fall of rice prices. Because of its unique drawing method, it is introduced into the analysis of stock market price trend. After more than 300 years of development, it has been widely used in stock, futures, foreign exchange, options and other trading markets.

This chart analysis method is particularly popular in China and even the whole Southeast Asia. Because the chart drawn in this way looks like candles, and these candles are black and white, it is also called yin-yang line chart. Through the K-line chart, we can completely record the daily or periodic market performance. After a period of trading, the stock price forms a special region or form on the chart, and different forms show different meanings. We can find some regular things from these morphological changes. The forms of K-line chart can be divided into reverse form, arrangement form, gap and trend line.

So, why is it called "K-line"? In fact, the word "K" in Japan is not written as "K", but as "Ku" (Japanese pronunciation reading kei). K-line is the pronunciation of "Ku line", and the K-line diagram is called "Ku line". In the west, the first English letter "K" is literally translated as "K" line. [ 1]