You're right. Each column represents the transaction volume. Each column in the time-sharing chart represents 1 minute, and the column height represents the turnover of this minute. As for why some are red and some are green. This is because the default decision in the system is to compare the current price with the previous price, that is, if the current price is higher than the previous price, it will display red, and if it is lower than the previous price, it will display green. The small column in this picture that determines whether it is red or green is the comparison between the closing price and the previous closing price. If you don't like this display style, you can also display red and green according to yesterday's settlement price in the personalized settings of system tools. In this way, if the current price is higher than yesterday's settlement price, it will be red, and if it is lower than yesterday's settlement price, it will be green.
The yellow line represents the trend chart of positions, and futures trading positions are a very important analysis index.