Reverse documentary means that when someone else makes a transaction, you use software to place an order with others at the same time. The same direction is forward documentary, and the reverse direction is reverse documentary. If you think others have a high profit probability, follow the positive documentary. If you think other people's profit probability is small, then follow the reverse documentary. As far as the futures market is concerned, the trading loss is far greater than the trading gain, which is the so-called market 28 law, so the strategy of reverse documentary is generally adopted. Because the direction of the other party's transaction is wrong, you follow the opposite direction, which is right, and the profit comes from it. Take-off data, in general, this is a reverse documentary system.