Futures trading software can always see the words "double flat", "empty cross", "double open" and "multiple cross" under the attribute column. What do they mean? I * * * how many such words? Please explain. Double flat: that is, long positions sell contracts and short positions buy contracts. Both sides are closed positions, so it is called "double flat"

Double opening: refers to the open position purchase contract. At this time, the short seller happens to open the position to sell the contract, and both sides open the position, so it is called "double opening"

Short position trading: that is, the short seller A buys the contract to close the position, and the short seller B sells the contract to A to continue shorting, that is, a short contract is transferred from A to B, so it becomes a short position trading.

Multi-exchange: that is, long A sells the contract and closes the position, and long B buys a long contract and continues to do more, that is, a long contract is transferred from A to B, so it becomes multi-exchange.