Foreign exchange transactions

Spot deal
A spot transaction is a two-day delivery transaction (except in the case of trades between the US Dollar, Canadian Dollar, Turkish Lira and Russian Ruble, which settle the next business day), as opposed to the futures contracts, which are usually three months. This trade represents a “direct exchange” between two currencies, has the shortest time frame, involves cash rather than a contract; and interest is not included in the agreed-upon transaction.
Notes:
Most spot deals take T+2 days
For Canadian dollar and Mexican peso settle on T+1 days,
South African rand, Thai baht with T+3 days
Saudi riyal (SAR) cannot be settled on friday due to religious reasons. So if you have USD/SAR trade on wednesday it will be settled on monday.

Forward


One way to deal with the foreign exchange risk is to engage in a forward transaction. In this transaction, money does not actually change hands until some agreed upon future date. A buyer and seller agree on an exchange rate for any date in the future, and the transaction occurs on that date, regardless of what the market rates are then. The duration of the trade can be a one day, a few days, months or years. Usually the date is decided by both parties. and foreward contract is a negotiated and agreement between two parties.

FX swap
In finance, a forex swap (or FX swap) is a simultaneous purchase and sale of identical amounts of one currency for another with two different value dates (normally spot to forward).
Transaction 1 : Spot deal on 2 currencies  where 2 parties agree to exchange on spot date
Transaction 2 : A forward transaction where teh currencies are re-exchanged at a forward date and at an agreed forward rate.

NDF (Non-deliverable funds )