All four are types of pending orders or, in other words, orders to open a new trade when the price reaches a predefined level.
Buy Stop and Buy Limit will be triggered when the Ask price reaches the specified level and Sell Stop and Sell limit will be filled at the Bid price.
- Buy Stop – an order to open a Buy position at a price higher than the current price level;
- Sell Stop – an order to open a Sell position at a price lower than the current price level;
- Buy Limit – an order to open a Buy position at a lower price than the current price level;
- Sell Limit – an order to open a Sell position at a price higher than the current price level.
As a rule, Stop orders are placed when the current trend is expected to continue and Limit orders when the market is expected to move in the opposite direction.