Basically, there are four types or orders:
- Buy Limit
- Sell Limit
- Buy Stop
- Sell Stop
Limit orders are usually placed when a person estimates that a price will reach a more favourable level (cheaper if she is planning to buy and more expensive if she is planning to sell) and then will change the direction. For example, if a person thinks that if EUR/USD falls down to 1.30, then it will start to move up afterwards, it would be reasonable for her to place a Buy Limit order at 1.30.
Stop orders are usually placed when a person thinks that if the price reaches a certain level, then it will continue to move in the same direction. For example, if a person thinks that if EUR/USD rises up to 1.60, then the pair will continue to move upwards, then she might want to place a Buy Stop order at 1.60.
Suppose, the green line is how to your mind the price will move in the future, then these will be reasonable orders to place: http://i.imgur.com/vjRKnnc.png