A user's current position on Drift is the cumulative sum of all their orders (increasing, reducing, or closing) over time. All trading lots are combined into a single position.
The position table then shows the Unrealised PnL for the current position. You can select to see in "$" or "%" terms.
Active trading may move funds between Unrealised PnL and Realised PnL.
The most important value is Total Collateral (Collateral + Unrealised PnL)
Currently, only the lesser of Free Collateral and Realised Collateral is available for withdrawal. Closing or reducing position will add to realised collateral available for withdrawal. In the future, Drift will add instructions to conveniently settle Unrealised PnL without trading.
A suggestion for users that want to stay in their position and withdraw unrealised profits in excess of their realised collateral is to close and reopen the position.
Read more in Trading Glossary