A position is a margin trade aimed at profiting from the rate changes. There are two types of positions:

Long (buy) is a position in margin trading that is opened by a buy order using borrowed funds and aimed at profiting from the rate increase.

Example: A user has 10 000 USDT on their balance. The price of 1 BTC is 10 000 USDT. To open a Long position with 5x leverage, the user can buy 5 BTC and close the position when the price increases to 11 000 USDT for 1 BTC. In this case, profit equals 5000 USDT.

Short (sell) is a position in margin trading that is opened by a sell order using borrowed funds and aimed at profiting from the rate decrease.
Example: A user has 1 BTC on their balance. The price of 1 BTC is 10 000 USDT. To open a Short position with 5x leverage, the user can sell 5 BTC and close the position when the price decreases to 9000 USDT. In this case, profit equals 5000 USDT.

Profit & Loss (P&L) is an amount of change of an open position compared to the current price. Thanks to P&L a user can estimate how profitable a position is at a certain moment. It allows a user to analyze and make decisions about an open position.

Example:

A Long position is opened.

Opening price: 10 000 USDT

Quantity: 5 BTC

Leverage: 5x

Current price: 11 000 USDT

P&L at the moment will be equal to 5000 USDT or 10%.