- Exchange is a highly organized market where (especially) tradable securities, commodities, foreign exchange, futures, and options contracts are sold and bought.
- Financial instruments are monetary contracts between parties. They can be created, traded, modified and settled. They can be cash (currency), evidence of an ownership interest in an entity (share), or a contractual right to receive or deliver cash (bond).
- Futures contract (or futures) is a standardized forward contract which can be easily traded between parties other than the two initial parties to the contract. The parties initially agree to buy and sell an asset for a price agreed upon today (the forward price), with delivery and payment occurring at a future point, the delivery date.
- A lot represents the standardized quantity of a financial instrument as set out by an exchange or similar regulatory body.
- Order is a <price, volume> pair.
- A limit order is an order to buy a security at no more than a specific price, or to sell a security at no less than a specific price.
- Immediate or cancel (IOC) orders are immediately executed or canceled by the exchange. An IOC order requires all or part of the order to be executed immediately, and any unfilled parts of the order are canceled.
- An order book is the list of orders that a trading venue (in particular stock exchanges) uses to record the interest of buyers and sellers in a particular financial instrument.
An order book is displayed as a table, in which prices are sorted upwards.
Green color signifies purchase, red one — sale.
- The bid and ask are the best potential prices that buyers and sellers are willing to transact at: the bid for the buying side, and the ask for the selling side.
- The bid-ask spread is the difference between the best bid and best ask prices.
- Deal is a purchase/sale of lots with an amount not exceeding the amount of an order. In other words, it's a matching (execution) of an order with another order in opposite direction.
- Position is the difference between bought and sold lots. It is positive if the customer bought more lots than sold and negative otherwise.
- Saldo is the outstanding balance is the amount of money owed (or due) that remains in a deposit account.
For example: if user bought 10 lots of instrument for the price of 1, and then sold 3 lots for the price of 2, then his current position is equal to 10 - 3 = 7, and his current saldo is
-10 * 1 + 3 * 2 = -4.