When a futures account opens a position, the position held after buying a futures contract is called a long position, referred to as a long position;

The positions held after selling futures contracts are called short positions, referred to as short positions.

The difference between open long contracts and open short contracts is called net position.

This only exists in futures trading, but not in spot trading.

Stock index futures, also known as stock index futures and futures index, refer to standardized futures contracts with stock price index as the subject matter. The two sides agreed that they can buy and sell the underlying index on a specific date in the future according to the size of the stock price index determined in advance. After a certain period of time, the two parties trade the price level of the stock index and make delivery by cash settlement of the price difference. As a type of futures trading, stock index futures trading has basically the same characteristics and processes as ordinary commodity futures trading.