Market Order:

Market orders are orders to buy or sell at the best possible prices as soon as possible. They are the first orders to be filled at any given price, and are used to enter or exit the market quickly, regardless of the current market price.
Example: Buy 1 March S&P 500 at the market
Market orders are generally not used in thin markets, where the fill could be substantially different from the last-trade price.

Market on Open Orders (MOO):

Market on Open orders are orders to buy or sell in the opening range; i.e.: within the range of prices traded during the opening period of trading.
If an order is placed "on the opening" with no stated price, it will be filled within the opening range. Example: Buy 1 March S&P 500 market on open

Market on Close Orders (MOC):

Market on Close orders are orders to buy or sell in the closing range; i.e.: within the range of prices trading during the closing period, anywhere from 30 seconds to 1 minute long.

Example: Buy 1 March S&P market on close

Good-till-Cancelled (GTC) Order

GTC orders remain on the books until cancelled.
Example: Buy 1 March S&P at 1220.00 GTC

One Cancels Other Order (OCO):

One executed order cancels an alternate order. These orders often are used when a price breakout is expected, but the direction of the breakout is uncertain.
Example: Buy 1 March S&P 500 at 1240.00 OCO 1250.00 Stop

Price Orders:

Entry Orders:

An entry order is an order used to enter a trade once a currency pair hits a pre-determined price level.

Entry Limit Orders:

An entry limit order is an order initiating an open position to sell as the market rises, or to buy as the market falls. The client placing an entry limit order generally believes the market will reverse direction at the level of the order.

• Buy Entry Limit
  A buy entry limit is an order to buy at a price below the current market
• Sell Entry Limit
  A sell entry limit is an order to sell at a price above the current market.

Entry Stop Orders:

An entry stop order is an order initiating an open position to sell as the market falls, or buy as the market rises. The client placing an entry stop order generally believes that prices will continue to move in the same direction as the previous momentum after reaching the order level.

• Buy Entry Stop
  A buy entry stop is an order to buy at a price above the current market.
• Sell Entry Stop
  A sell entry stop is an order to sell at a price below the current market.

Limit Orders:

A limit order is an order linked to a specific position for the purpose of locking in the gains from that position, while a limit order placed on a buy position is an order to sell. A limit order placed on a sell position is an order to buy. All limit orders remain in effect until the position is liquidated or cancelled by the client.

Market Order:

A market order is an order to buy or sell which is to be filled immediately at the prevailing currency price.

Stop-Loss Orders:

A stop-loss order is an order linked to a specific position to close that position and prevent additional losses. A stop-loss order will be executed when the displayed price on the platform touches the order price. The executed price will be the order price or in the case of a fast market the order will be executed at the next displayed price. When a stop-loss order is placed on a buy position it is an order to sell that position. While a stop-loss order on a sell position is an order to buy that position. All stop-loss orders remain in effect until the position is liquidated or cancelled by the client.

Stop Order:

Stop orders are not executed until the market reaches a given price, at which time they become market orders. They are normally used to liquidate earlier positions.

Stop orders can be used to enter the market. Suppose you expect a bull market (rising market) only if the price passes through a specified level. In this case, you could enter a buy-stop order to be executed if the market reached this point.

Stop orders may be inappropriate in very thin or choppy markets, and in any case, placement must be varied depending on price volatility.