linear: linear contract (USDT-margined contract), which uses USDT or other stable coins as quote currency, settlement currency, and margin.
inverse: inverse contract (Coin-margined contract), which uses the base currency for both settlement and margin, while USD is used as the quote currency.
isolated: isolated margin. In Isolated Margin mode, the margin for each position is separate and cannot be shared with other positions. The system won't add margin automatically, and any additional margin needs to be manually added by the user.
cross: cross margin. In Cross Margin mode, all available balances in the Futures account can be used as a shared margin for all current positions. To avoid forced liquidation, the system will add margin automatically by using the available balance in the Futures account.