A swap, also known as a “rollover fee”, is charged for keeping a position open overnight.
A swap is the interest rate differential between the two currencies of the pair you are trading.
Short (Sell) or Long (Buy) is the term used depending on the position you are trading.
To assess your profits/losses, you may use the below formula:
What are the "One Point" and "Trade Size"?
Trade Size = Lots * Contract Size = 100,000
You can check the swap values, contract sizes, swap long, swap short and triple swap days for different instruments in the Symbol properties window on the mobile app. On the desktop app right-click on a symbol in the Market Watch window and select "Specification".
So, if we were to apply the above information into an example: